Music, chess and mushrooms

Pawn Tension part 1 (a wee lesson)

2011-12-03T20:45:00.000-08:00

Well, I've played a lot of chess recently, and I seem to have a lot of it bubbling out of me, so hopefully this is the start of some more frequent posts ("more frequent" being a standard that is not hard to exceed). However, I do have a lot of other stuff bubbling out of me also, so we'll see which upwellings win the battle for my time.

This post (and hopefully a related one to follow) are explorations of the issues of pawn tension. It’s funny the way sometimes you see something basic in chess and then you start seeing it all over. I played a friendly game with a co-worker yesterday, and afterwards he asked me where he went wrong. I drew his attention to this position:
1. d4 d5 2. Nf3 Nf6 3. e3 Bf5 4. c4 c6 5. Bd3 Bxd3 6. Qxd3 e6

At this point, White pushed his c-pawn another square forward, which is something you should never, ever do. In fact, my computer Fritz’s evaluation of the position instantly goes from completely equal in the diagram to .4 pawns advantage for Black after White pushes the c-pawn.

The main concept here is pawn tension. In the diagram, there is tension between the black pawn at d5 and the white pawn at c4, which are mutually attacking each other. This means that Black can’t take action in the center without taking into account what might happen if White cashes in on the tension by capturing on d5. By pushing on past, White gets rid of the tension, thus giving Black a free hand for his own operations. In fact, Fritz’s preferred method of exploiting the push to c5 is for Black to play b6, immediately re-establishing pawn tension on a pair of squares that White has less control over:

This shows another reason why the push of the c-pawn is bad: it makes White’s bishop a worse piece. At this point, all of White’s center pawns are on dark squares, hemming in his remaining bishop. This is called a “bad bishop”. By contrast Black has a “good” bishop: its pawns are on squares of the opposite color. Perhaps White pushed the c-pawn in part to restrict the action of Black’s bishop, but you can see that this “restraining” pawn has become a target. In a way, the overall dynamic of this contrast is the same: White’s bad bishop can’t attack Black pawns (which are on the other color) so Black’s hand is free to do things like attacking pawns with his bishop.

In the actual game, after a few more developing moves,

Black got to play 12…e5. If Black had still needed to consider the consequences of a capture cxd4, this would have needed a whole lot more calculation. As it was, I just needed to see that there’s a potential pawn fork if the e-pawn continues forward; and after an exchange on e5, the c-pawn may also be vulnerable. After a few more exchanges in the center,

I got to play my knight to c4 (the square that White refused to contest at the very beginning), attacking both of White’s minor pieces. After 19…Nc4 20.Nb1 cxb5 21.Rxd5 b4 22.Bc1 Rfd8 I exchanged all the rooks on the d-file and my queenside pawns made a touchdown – precisely on the side of the board where White had originally advanced his own pawns.

After the game, I told my friend that his strategy had been discredited in the 1880s. I was thinking of a couple of games from the world championship match between Steinitz and Zukertort, and when I went and looked them up, it was clear why I associated them with this sort of pawn-play. They’re very cool games:

Johannes Hermann Zukertort - Wilhelm Steinitz
World Championship Match game 1, 1886

1.d4 d5 2.c4 c6 3.e3 Bf5 4.Nc3 e6 5.Nf3 Nd7 6.a3 Bd6

Look familiar? White now pushes he c-pawn forward; and on the next move, Black achieves the …e5 push
7.c5 Bc7 8.b4 e5

As in our stem game, White’s Bc1 is colossally “bad”, and Black is in control of the central tension. Black’s Bf5 is also bad theoretically; but since it’s outside the chain of black pawns, it’s a much better piece than White’s QB.
9.Be2 Ngf6 10.Bb2 e4 11.Nd2 h5 12.h3 Nf8 13.a4 Ng6 14.b5

Over the next past moves, Black has brought his knights over to the kingside and killed the pawn tension in the center, thus making sure that nothing significant is happening anywhere on the board except the sector where he plans to attack. He loved maneuvers like his Nf8-g6 here, building up a slow attack with his king still in the center. Now the knight continues his mission:
14…Nh4
The available ways of defending the g-pawn all involve some sort of positional concession, so Zukertort just pushes it, and then…
15.g3 Ng2+!? 16.Kf1 Nxe3+ 17.fxe3 Bxg3 18.Kg2 Bc7

Steinitz has give up his charging knight for two pawns in order to expose the White king. Because the rest of the board is all locked up, he can continue feeding pieces over there without much else happening. White has to find some really precise defensive moves to neutralize this very nebulous attacking setup, and Zukertort isn’t up to the task:
19.Qg1?

He’s getting the queen out of the way so that his king can run back to the center (and hopefully even the queenside) but this is the wrong way to do it. He should move the queen to f1, overprotecting the h3 pawn and gaining a tempo by attacking the undefended Bf5. After the bishop retreats, White can play Kf2 and the king will continue his run to safety. Then the game will go on; Fritz thinks that White has a slight advantage, but there isn't any clear plan on the board for him to undertake.

In response to Qf1, Black must retreat the Bf5, since after
19.Qf1 Qd7? 20.bxc6 bxc6 21.Nb5!

White is suddenly doing very worthwhile things on the queenside. Black can’t capture the knight since the bishop recapture pins his queen. And Black’s queen can’t defend both bishops at the same time, so after 21…Be6 22.Nd6+! Black doesn’t want to leave the knight sitting there in the heart of his position, blocking the attacking Bc7; but after 22…Bxd6 23.cxd6 Qxd6 24.Ba3! suddenly White’s “bad” bishop is very actively placed, and after 24…Qd7 25.Kf2 the White king continues his trek to safety.
As it is, after
19.Qg1? Rh6 (threatening to win the queen with Rg6+) 20.Kf1 Rg6 21.Qf2 Qd7 22.bxc6 bxc6

with Black’s rook already in attacking position at g6, White has no time for Nb5 here, because after 23.Nb5 Bxh3+ 24.Ke1 Bg3 White’s queen is pinned and lost. Black will just move his king in response to Nd6+ here. So White must defend g3 with another piece:
23.Rg1 Bxh3+ 24.Ke1 Ng4 25.Bxg4 Bxg4 26.Ne2 Qe7 27.Nf4 Rh6 28.Bc3 g5 29.Ne2 Rf6 30.Qg2 Rf3!

Steinitz must have enjoyed making this move: he always did say that you should attack a pawn chain at its base. If you compare this diagram and the previous one, you’ll see that Steinitz’s pieces have been moving forward while White’s are basically just shuffling around. That trend will continue.
31.Nf1
If 31.Nxf3 exf3 32.Qf2 fxe2 then Black has just gotten two knights for his rook; factoring in the knight that he originally sacrificed, and the pawns he’s picked up along the way, that leaves him with three pawns for the exchange, a massive material advantage.
31...Rb8
Steinitz adds insult to injury by taking control of the open file in White’s preferred sector of the board.
32.Kd2 f5 33.a5 f4 34.Rh1 Qf7

Black has just kept building up. It’s now impossible for White to avoid the loss of major material.
35.Re1 fxe3+ 36.Nxe3 Rf2

The White queen’s only flight square is g1; but then Qf3 comes and the Ne2 falls, then the king behind it. So….
37.Qxf2 Qxf2 38.Nxg4 Bf4+ 39.Kc2 hxg4 40.Bd2 e3

This seems to have been a tremendous time scramble, but even so I think I would have been embarrassed into resigning at this point. Note, however, that Rh8+ doesn’t win Black’s rook, as it is protected by his bishop. Given what happens later, that might have been a good try, though.
41.Bc1 Qg2 42.Kc3 Kd7 43.Rh7+ Ke6 44.Rh6+ Kf5 45.Bxe3 Bxe3 46.Rf1+

Yes, apparently this really happened in a world championship game: White gives check with an unprotected rook next to the black queen, and Black doesn’t take it. One for the ages.
46…Bf4 0–1

Okay, this is enough for the moment; hopefully I’ll be posting the second Zukertort-Steinitz encounter and another relevant game anon.

You gotta love it

2011-09-24T20:47:00.000-07:00

This sort of victory is probably at least partially responsible for my poorer tournament results, but you’ve still gotta love it when something like this happens:

Shernoff-Count Mulningsvelin, FICS blitz 2011
I am giving my opponent the title of Count, because he generously did his best to make me look like Paul Morphy in that opera box...

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. f4 Qc7 7. Bd3 Nbd7 8. Nf3 b5 9. O-O b4 10. Ne2 Bb7 11. Ng3

We have a fairly normal Sicilian

11...Nc5 12. Qe1 a5 13. Bb5+ Bc6 14. Bxc6+ Qxc6 15. e5 dxe5 16. fxe5 Nfe4 17. Ng5 Nxg5 18. Bxg5 Ne6 19. Be3

It’s now an even more typical Sicilian in that Black has (a) no development (b) no presence in the center, but is still okay. But now Black goes crazy and starts grabbing pawns – not a recommended action when your opponent can bring all three major pieces to the center, where your king is.

19...Qxc2

I was anticipating 19... g6 20. Qf2 Nd8 and I wasn’t sure how to proceed. Fritz then makes the easily-findable moves 21. Bb6 Qe6 22. Ne4 Bh6 and awards White a clear advantage from opening up the queenside with 23. a3!
After Black's capture, I considered preserving my precious queenside pawns with 20.Rf2 and Qf1, with threats against f7 and b5, but I decided that my queen would be better off on d1, ready to come to f3 which is strong...

20. Rc1 Qxb2??
I didn’t give Black’s previous move a question mark because Fritz actually thinks it’s the best move! But that’s only because it follows up with 20... Qd3, keeping my queen off d1.
21. Qd1 Qxe5?
and here f3 is of course still a winning possibility; but Black’s kind capture on c2 has opened up a new diagonal for my queen:
22. Qa4+

22... Kd8 23. Rfd1+ Qd6 24. Bb6+ Nc7 25. Bxc7+
1-0

Fourth of July games

2011-08-11T08:19:00.000-07:00

For a few years now, my friend and neighbor Tom Panelas has been running a bank of chess boards at our local fourth of July shindig it the park down the street from where I live. This year, I showed up fairly early and ended up manning two boards for most of the afternoon, mostly against kids who were under 10 in age and under 1000 in playing strength. I did have one tremendously entertaining game, though, against Adam J, captain of the Wendell Philips High School chess team, and I wanted to share it because it’s become sort of a tradition for me to tremendously embarrass myself on the internet at least once a year.

But first I wanted to share a game against one of the few grown-ups to challenge me, just to show that I had some measure of general coherency during the afternoon. This game started off as a fairly normal English:

Grown-up - Shernoff [A20]
Nichols Park 4th of July, 04.07.2011
1.c4 e5 2.e3 f5 3.a3 Nf6 4.Nc3 g6 5.d3 Bg7 6.Nf3 Nc6 7.b4 0–0

After it was no longer an issue, I noticed that White could have taken my e-pawn after b4-b5 around here. Here, it doesn’t really work, because of 8.b5 Ne7 9.Nxe5 Ng4 and Black gets into trouble on the long diagonal. But he should definitely do it on the next move, or play Be2 and castle, because he ends up wasting too much time with these meaningless pawn moves on the queenside.
8.Bb2 d5 9.c5?!

Okay, I’ve got the big center, he isn’t castled but I am, ergo I should push a center pawn. The f-pawn is keeping a knight off e4 for me, so I think I’ll push the d-pawn.

9...d4 10.Qb3+ Kh8 11.exd4?! (better is 11.Ne2) 11...exd4!?

After 11...Nxd4 12.Nxd4 exd4 13.Ne2 Re8, Fritz awards me an advantage of .69 of a pawn, but this isn’t likely to result in the sort of game I want to play outdoors on a hot afternoon.

12.Nb5?

This looks natural and aggressive, but it’s wrong, because the knight doesn’t have a safe retreat. After 12.Ne2, Fritz rates the position equal, as it doesn’t trust my ability to hold the pawn at d4 after the upcoming b4-b5 push.

12...Re8+ 13.Be2

13...Nd5
and again, this is an overplay, but I was pretty sure he’d grab the d-pawn. Better is 13...Nh5, when I’m holding the d4 pawn solidly and White can’t stop both Nf4 (with trouble for the Be2) and a6 (with trouble for the Nb5).

14.Nbxd4? (14.g3 is the only move) 14...Nf4

15.Nxc6
This is a natural move: White gets rid of his en-prise piece while attacking my queen, and is ready to exchange his Bb2 with check, thus preserving it from capture. However...

15...Rxe2+ 16.Kf1 Rxb2
Whoopsies!

17.Qxb2 17...Qxd3+ 0–1

Okay, on to the main show. It is essential to realize that I had just been playing for two or three hours against small children and my whole attitude was focused on playing quickly and grabbing material (the above game was played after this one). It took me a while to adjust when faced with a real player.

Adam J - Shernoff
Nichols Park 4th of July, 04.07.2011
1.h4

Oh! He’s one of those players. Wants to bring the rook out first. Well, I can cover h3 with my bishop.

1...d5 2.h5

Hmm. A new square for his rook. Well, I can cover that with my queen.

2...e5

3.h6
Man, he really wants to bring that rook out, doesn’t he? At this point, I’m not expecting the game to be very difficult.

3...Nxh6 4.Rh5 Nc6 5.Nf3 Bd6?!

I was just thinking in terms of sitting tight in the center without thinking too much and waiting for him to hang something. Fritz already wants me to start playing more constructively with moves like
5...e4, which I will follow up with other moves like Qf6 (if 6.Ne5 then 6...Nxe5 7.Rxe5 Be6 first), Bc5, and 0-0-0. Black dominates the center and is efficiently developed.

6.Nc3 Be6 7.a4 Qf6 8.a5

8...a6?

Stupid, stupid, stupid. I actually thought “Well, if I don’t fix the pawn here, he’ll just push it another square and I’ll have to lose a tempo playing b6 anyway.” Of course if that happens then – Hello! – he’ll have lost another tempo ALSO, pushing the pawn that extra square.
Sadly for the future quality of this game, Adam is playing badly enough (with this “push both rook pawns” garbage) to convince me that he’ll soon tank, but without actually playing badly enough to instantly lose. Well, that’s not true – White had a fairly crushing line here if he’d just started to think positively and targeted f2, instead of just waiting for a blunder:
After 8...e4

9.Ng5 (9.Ng1 Qxf2+! 10.Kxf2 Ng4+ and Bg3#) 9...Ng4 and white is forced to take twice on e4 with his knights, as 10.Nh3 is met by 10...Nxf2 11.Nxf2 Bg3. Sadly, this line remained unplayed.
Instead,

I realized that I had to start playing constructively here, and decided to cleverly play Nb4 and Qg6 here, threatening the brutal Nxc2+ and the Rh5. Unfortunately, I violated basic chess precepts like “Hey, he gets to make moves also” and “BTW, you should pay attention to what those are.”

8...a6 9.Ra4 Nb4 10.d4

10...Qg6?

By now I really should react to him in the center and take the d-pawn, but then he takes back with his knight which then defends c2 and I’d have to think of something new to do and do a bunch more calculating, and it was too hot for that, plus the little kid on my other board kept yelling at me to move more quickly, and...

11.dxe5 Qxh5 12.exd6

Ooops! Now my Nb4 is hanging, and I react badly...

12...Nc6? (12...c5!) 13.dxc7 0–0

Now I figure I’ll just round up the c7 pawn and crush him... somehow. In fact, Fritz calls this position equal, a measure of how badly I’ve played over the last few moves. And as often happens when you’ve blown an advantage but don’t realize it, I get frustrated trying to find good lines that aren’t there anymore, and make matters worse. Much, much worse.

14.Qd3 Rac8 15.Ng5

Hey! He’s threatening mate! How’d he do that?

15...Nf5??

Way dumb. I was concerned about not only blocking the mate, but getting my knight back into play and having my queen defend against the mate so the knight could move again. I just didn’t calculate. After 15...Bf5 16.Qxd5 Rxc7 Black is doing all right again.

16.Nxd5??

16.g4, forking my queen and knight, is, umm, much stronger.

16...Ne5??????

There’s a game against Portisch where Vlastimil Hort says “My hand should be cut off for making this move.” This is that kind of move. It’s wrong on just so many levels.
First of all, I saw perfectly well that he would just play Qe4 and my knight can’t be maintained on that square, so he’ll get to capture on e6. Second, since in my pride I want to pretend that I moved the knight to e5 for a reason, so I won’t retreat it to c6, which is in fact its best square.

17.Qe4 Ng6 18.Nxe6 fxe6 19.Qxe6+ Kh8 20.Rc4

Hey! Did I mention that my knight should really be on c6? White now has a colossal advantage. Among his threats is Nb6. I play yet another move without thinking, simply making stupid threats by reflex under the theory that eventually he’ll just screw up on his own:

20... Rfe8?? 21.Qxe8+! Rxe8 22.c8Q

Hey! Did I mention that my knight should be on c6?
Now I really had to do some thinking. I’m down a piece and a pawn, and I’m going to lose more pawns on the queenside because of his back-rank threats.

22...Nge7!?

Fritz wants me to fork immediately with 22...Nd6 23.Qc5 (23.Qd7 Qxd5) 23...Nxc4 24.Qxc4. I regarded this as insufficient (Fritz rates White as ahead by 3.2 pawns) and went for a potentially bigger regain of material.

23.Qxb7 Nd6 24.Qxa6

Did I ever mention that it was stupid of me to push this pawn to a6? Did I?

24...Nxc4 25.Nf4??

Adam sees that if he recaptures on c4, I’ll capture on d5. But that just means that he should put that hanging piece on d5 to work first, and capture 25.Nxe7! Then there’s really no hope for me. Now I’m still nominally behind in material, but I have chances because his development is so poor. On the other hand, I still have back-rank problems and he’s got an a-pawn that’s pretty close to queening. Still not any easy game for either player.

25...Qc5

He needs to move his e-pawn one or two spaces here and get his bishops out. But unfortunately I think he decided that defending the a-pawn was important. It is, I suppose, but not as much as his development. And if he can get the queens off along with that, so much the better: 26.e3 Nxa5 27.Qb5, hitting e8, and his remaining queenside pawns will roll me up.

26.Bd2?? Nxb2?

26...Nxd2 27.Kxd2 Qb4+ would have won the Nf4, but who’s calculating when I can just enter his position like this?

27.f3?

This is a pretty awful move, but it’s actually really difficult to play White’s position now. After 27.Nd3 Qxc2 28.Nxb2 Qxb2 29.e3 Qa1+, White loses coordination. So the very best move is 27.c3!!, so that White can play Nd3 on the next move without losing the c-pawn. Then 27. c3 Nd5 28.Nd3 Nxd3 29.Qxd3 and Fritz calls this position equal. These two are by far White’s best lines, which shows how careful he has to be here.

27...Qxc2 28.Qb5 (Maybe I’ll drop the rook) Rd8 29.Bb4 (Maybe I’ll drop the knight) Nf5
Now he’s making it obvious, but Adam’s actually been playing little one-mover threats for a long time now. It’s almost as if he’s caught my disease from earlier in the game.
30.a6 Qc1+ 31.Kf2 Nd1+
Yes, I actually missed a mate with 31...Qe3+ 32.Ke1 Rd1
32.Kg1 Nde3 33.Qb6

Okay, showtime! I’ve got one hell of a bind, and the Bf1 is evaporating, but my Rd8 is also hanging with mate, and I don’t want to put it on g8 and have him try to conjure some smothered mate (or Ng6+ & Q-h-file mate) or queening his a-pawn... I wanted it to be over, quickly and permanently. So I enlisted the help of Susan, the vastly underrated little girl on the other board (“Hey! That’s cheating!” said Adam) to check my calculations as I finished things off with checks.

33...Qxf1+ 34.Kh2 Ng4+!

Susan had not anticipated this, but she felt very proud of herself for being able to calculate that on 35.fxg4+ Qxf4+, 36. Kh3 Qg3 is mate, and if the white king steps back instead (before or after 26.g3 Qxg3+) then Rd1 mates. So Adam didn’t take the knight, but after

35.Kh3 Nf2+

Susan was shocked to discover that 36.Kh2 is met by Qh1#, so Adam played
36.Qxf2
and the rest of the game wasn’t that difficult.

What a fourth of July!
More games from the Skokie tournament that I won coming in a bit...

May tournament round 1

2011-07-28T14:38:00.000-07:00

Hello, everyone!

I’ve finally gotten a few moments to start answering the questions in the quiz I posed a while back.

Actually, I’m going to do that by going through my games from the May tournament that I won. There’s a surprising amount of stuff in some fairly simple-looking games. This is the first game in that tournament, and the answer to the first quiz position.

But first another little quiz:
White has given check, seeking compensation for his pawn minus in his bishop pair and better development:

There are themes of Re7+ if the king moves to the second rank, and Kd8 is met by Nxg7 followed by (...Rf8, Nh5) Bxf6+. What about Kf8, which avoids these problems?

Okay, here's the game:

Vytas Vytsauskas - Leon Shernoff [A27] Skokie G/90, 5.6.2011

after a mutually misplayed opening, we reached this position. I was definitely playing myself back into shape in this first-round game, and for some reason couldn’t see any difference between the various Nc6 moves! I knew I was going to play …d6 and …b6 soon and then the knight(s) dance to those squares and onwards; I wasn’t seeing any difference in where they went first. Luckily, at the last minute my hand reached out and threw the knight onto a5 without any conscious intervention on my part.

Also part of the "playing myself back into shape" thing: I thought I was okay at this point, but it turns out I’m definitely not!

9… Na5 10.Qxe7+ Kxe7 11.Bd3 h6

Black is playing very slowly and for the greatest possible advantage: I see that my knights can kick the butt of White’s doubled pawn complex, so I don’t want him to be able to exchange one of them with Bg5.

The course of the game will show what I was aiming for, since it gets implemented pretty much without opposition. It may seem a little strange here, but White should have taken a bunch of moves to exchange his bishop and inflict a similar weakness on Black: 12.Ba3+-b4xa5 was best. Fritz then gives White an advantage of almost a pawn.

12.0–0? b6 13.Nd4?!

Similarly, even here, better is 13.Re1+ Kf8 14.Ba3+ d6 15.Bb4 Nb7 and suddenly White’s space advantage is actually useful and his pieces aren’t tied down to his weaknesses like they end up in the game.

13… Ba6 14.Nf5+

At first, I was worried about 14.Nb5, because I consider Vito a better calculater than I am; and there’s lots of stuff that could go wrong for Black after this move. But 14…Bxb5 15.Re1+ Kd8 16.cxb5 Nxd5 is safe enough.

14...Kf8 15.Ne3 d6

16.Bd2?!

Again, the bishop should go to a3 to exchange off the first knight that appears on c5. On d2 it is just in the way, and something of a target.

16…Nd7

How should White respond to this move? It threatens Ne5, irrevocably winning a pawn, and thus provokes 17.f4. But it’s not hard to see that White will lose a pawn soon anyway, so maybe it was better to just try and get active and avoid making this new weakness. After all, once Black takes on c4, that opens things up a bit for White’s bishops. Fritz has White only down half a pawn after
17.Rfe1 Ne5 18.Bf1 Nexc4 19.Rad1

which is way better than the game continuation.

In fact, if Black takes on c4 with the bishop to avoid the pin:
18...Bxc4 19.Nxc4 Naxc4 20.Bc1 g5 21.Re4 Na5 22.f4

Fritz calls this position equal, though I respectfully think that the extra pawn is still a pawn here. Granted, neither of these is a position that White wants to achieve out of the opening; but it’s loads better than what actually happens to him.

The question of whether White can/should just shed a pawn early and try to get compensation through the opening of the position for his bishops will keep recurring over the next several moves.

17.f4 Nc5 18.Be2 Re8

This is the position that I put up as a quiz last month. The question is how to respond to Black’s pressure on the e-file. In fact, my main concern here was how to get my Rh8 into action. If I play …g6 (instead of Re8), intending …Kg7, then he plays f5, and suddenly it looks like his kingside pieces are doing something real. Likewise, after …f6 he has Bh5, and I don’t want this to happen either. I could walk my king to h7; but that’s way lame considering how much time it takes and considering that since we’re on the verge of an ending, the king will soon have to walk all the way back to the center. So I decided to probe by developing the other rook, and see if I could develop my pieces this way.

19.Rf3?!

After this, Black achieves a total bind unhindered. I thought that White had to try 19.Kf2, protecting both pieces on the e-file, as after the game move I have 19…f5, solving my development problems and fixing the weak Pf4.

Well, it turns out that 19.Kf2 loses a pawn to Ne4xc3 and Rxe3 – in fact this is a general threat of 18…Re8 (so Fritz in fact also prefers 19.Rf3). I hadn’t noticed this at all during the game (like I said, I was definitely playing myself back into shape at this point) because I was mainly concerned with how to get the Rh8 into play. However, shedding a pawn is not necessarily bad for White if it opens up things for his bishops and gets his pieces active. There are two ways to attempt this: 19.Kf2 and 19.Rae1.

As Todd pointed out, 19.Kf2 has the flaw of not developing further, while uncastling the king. On the other hand, it turns out to allow Bxa5 (finally!), which almost balances out these flaws:
19.Kf2 Ne4+ (19...Re4!? ×f4, c4) 20.Ke1 Nxc3 21.Bxc3 Rxe3 22.Bxa5 Bxc4

(looks scary, but…) 23.Rf2 bxa5 24.Kd2 Rxe2 25.Rxe2 Bxe2 26.Kxe2 with a rook and pawn ending that most of us humans would consider quite blowable – Black has two extra pawns, but one them is doubled and isolated, and the other is backwards on an open file. Plus, White is about to activate his rook first.

Certainly, White’s chances are way better than in the game.

19.Rae1 looks much more constructive, and (but?) carries with it the possibility (risk?) of much more active/dynamic/complex play to justify the additional material sacrifice. In short, this is the line to go for if you think White should be pursuing radical remedies here:

19…Ne4 20.Bc1 Nxc3 21.Bd3

and now Todd gives
21...Ne4 22.Bb2 Nf6 23.g4
when White has full counterplay. Fritz plays more dynamically for Black, giving 22...Nc5 (instead of Nf6) 23.Nf5 f6 24.Rxe8+ Kxe8 25.Re1+

and awards Black an advantage of a third of a pawn, but the possibilities here of Re7, or (…Kd8) Nxg7-h5 render this fairly meaningless in human terms.

Quiz Answer!
The move that best avoids these possibilities, 25…Kf8??, sadly runs into 26.Nxd6! with back-rank awfulness (26...cxd6 27.Bg6).

In any case, the two bishops and the undeveloped Rh8 are really showcased in these lines. Black’s extra pawn is fairly meaningless at the moment.

However, Black has a more dynamic possibility himself, grabbing another pawn with 21…Nxa2 (instead of 21…Ne4), and the black knights start to dance on the queenside:

21…Nxa2 22.Ba3 (22.Bd2 Nb3) 22...Nc3 23.Bb4 Na4

Finally, the white bishop has reached b4, but it’s not enough. White has two possibilities, and both are fairly messy, but they also seem fairly won for Black (given enough time):
24.Bc2 Nc5 25.Bxa5 bxa5 26.Kf2

and White is ready to play 27.Ra1, but this doesn’t seem like enough.

The other line is

24.Nf5 Nc5 25.Rxe8+ Kxe8 26.Re1+ Kd8 27.Bf1 Bxc4 (27...g6 28.Nd4) 28.Bxa5 Bxf1 29.Kxf1 bxa5 and White is down three pawns at the moment.

After taking on g7, Fritz rates Black's advantage at only 1.3, which again is much less than in the game, but still should really be losing, especially as it's much harder for White to get at Black's queenside pawns in this line.

At any rate, we can now appreciate the complications that White could have spawned, instead of the continuation in the game where Black just gets to sit on him without worries:

19.Rf3?! f5! 20.Kf1 g6

Now I have a choice of developing my kingside with Kf/g7 and Re8, or Rh7-e7.
Fritz prefers to swoop in immediately with

20...Re4 21.Re1 Bxc4 22.Nxc4 Nxc4 23.Bc1 b5

which indeed looks quite dominating. But it only gets this far by rejecting (20...Re4 ) 21.Nxf5 Nxc4 22.Bxc4 Bxc4+ 23.Kg1 Bxd5

when White has genuine activity, potentially meaningful pawn imbalances, and opposite colored bishops. To a human, this is much less attractive for Black than what happens in the game. Especially in a G/90 situation, the trouble-free situation is the one to go for.

Back to the game:

21.Rd1 Re4 22.Be1 Bxc4

White is ready to defend his c-pawn with Rd4, so Black needs to take.

Depending on your point of view, my move is either an inaccuracy or a clever trap. I wanted to exchange two pairs of minor pieces, which I can force by 22...Nxc4, but I didn't see that my Ba6 was defended, so thought I had to take with the bishop first.

23.Nxc4 Nxc4

24.Bxc4

All’s well that ends well: he decides to trade everything anyway. Fritz tries to keep the minors on, but then finds out that this loses more material (this would be the clever trap): 24.Rd4 Ne3+ 25.Kg1 (25.Kf2 Ng4+ 26.Kf1 Nxh2+) 25...Nxd5.

24...Rxc4

25.Rd4?
This is a big mistake, as now White can’t avoid the loss of another pawn via the following maneuver, and he’ll be left with an awful minor piece. Correct was
25.Bf2 Ne4 26.Bd4 Rh7
when White’s only one pawn down with a lousy position, and Black will have trouble making progress without allowing the exchange of his knight. As the game goes, White not only loses another pawn, his bishop is a huge albatross around his neck.

25...Rxd4 26.cxd4 Ne4 27.Ke2 Nf6 28.Kd3 Nxd5 29.Kc4 c6 30.a4 a5 31.h3 h5 32.Bd2 Kf7 33.g3 Re8 34.Kd3 Re4 35.Kc4

There has been none of the White counterplay we’ve seen in the earlier sidelines. Fritz awards Black a 3.6 pawn advantage, even though White is only two pawns down on the board and has the more centralized king.

Now Fritz wants Black to play 35...Nc7 (with the idea of c6-c5) 36.Rd3 d5+ 37.Kc3 h4 38.gxh4 Ne6 at which point it gives Black a four-pawn advantage. However, I stick to my ultra-solid style of cashing in:
35...Re2 36.Kd3 Rh2 37.h4 Rh1 38.Kc4 Rb1 39.Ra3

Now that my Rb1 is holding my one weak(ish) pawn on b6 (against Rb3), I can swing my knight to e4, causing White’s bishop a bit of embarrassment. I’m hoping for something like (magically move Black’s knight to e4 in the above diagram) Kd3 Rd1 Ra2, or Bc3 Rc1 where the bishop is pinned, and I get to exchange all the pieces, leaving me with a dead-won pawn ending. I like dead-won pawn endings. But even without that, the next order of business is N-f6-e4 and Ke6-d5.

Best for White is probably (39…Nf6) 40.Kd3 Ne4 41.Be3, but there’s no doubt about the outcome after I bring my king to d5. Instead, White blunders.

39...Nf6 40.Rb3?? d5+ 41.Kc3 Ne4+
0–1

because of …Rxb3 and Nxd2

Chess Quiz

2011-05-18T22:14:00.000-07:00

Hi there, everyone

Here are some positions that I've recently either played or come across. See what you can make of them. I'll post complete games (for the games that are mine) soon, but in the meantime feel free to suggest answers here.

These aren't traditional "White to move and win" problems, but have more of the messiness and uncertainty of the situations in which we actually make most of our decisions over the board.

1)

Black is doing the Nimzovich "restrain and blockade" thing on the queenside, and he steps up the pressure with
16...Nd7 17.f4 Nc5 18.Be2 Re8, giving us this position:

How should White respond to the pressure on the e-file?

2)

Black has just played the moves 7...e5xf4 8.Be3xf4 Qa5-b6, forking White's pawns at b2 and d4. How should White respond?

3)

After this game was over, one of the other players told me "You could have won on move 12! Just play e5 and sac the bishop on h7!" Was he correct? Does 12.e5 Nd5 13.Bxh7+ win?

4)
Later in the game, I did manage to play Ng5 and Bxh7+ (without saccing anything) but in the meantime Black managed to get the queens off and find annoying outposts for his knights:

Find a win for White. There are actually two ways of implementing the same idea.

5)

Black to move. His next two moves are going to be 47...Kc3 and 48...Kxb3. What should White's next two moves be?

6)

Black has just played 11...Be7 here. What's the idea behind this move? What issues does it raise?

A few moves later, this position arose. White has been building up for some time now, has a lead in development and greater center control, and has been looking for a knockout. What should he play?

7)

My opponent made a "known error" in the opening and is about to lose one of his knights. After 17...Nxd4 he got happy again and played 18.Nb5. I think he was hoping the pin on the d-file would allow him to regain the piece but 18...Bg4 corrected that. Now after 19.Re1

I can maintain my extra piece plus get the queens off with Nxb5. However, my opponent is ten years old and won't resign unless he's faced with something like mate or loss of his queen. Make him resign.

8)
A fun one for the end:

White has just played 18.h3. What is Black's best line here? And after 18...Nxd3+ 19.cxd3 Bc8 20.g4 f6 (which is not Black's best line):

How should White win?

Bonus points: spot the thematic similarity between this situation and the one in the previous question.

Let me know what you think!

I do well in a tournament

2011-04-20T19:39:00.000-07:00

Hello, everyone! I’ve been meaning to post some games/positions from the training I’ve been doing, and will be ready to do that soon; but I placed second in a G/45 tournament this past weekend and got quite a nice response on FaceBook to my posting about it; so I thought I’d put up a game from that tournament first, since this can be done more quickly.

This game was played in the third round, when we were both 2-0.

Leon Shernoff - Chris Girardo
North Shore Chess Center G/45

1. e4 c6 2. d4 d5 3. exd5 cxd5 4. c4 Nf6 5. Nc3 Nc6 6. Nf3 Bg4

One of the main lines of the Panov-Botvinnik Attack in the Caro-Kann. I have had two utterly wretched games in this opening before with 7.Be3 here, and luckily one of them took place online just a couple of weeks before this game and it embarrassed me into actually looking up a few further moves in my Caro book. My opponent was also clearly booked up, playing his moves almost instantly.

7. cxd5 Nxd5 8. Qb3 Bxf3 9. gxf3 e6 10. Qxb7 Nxd4

You have to admit this is an entertaining position to reach in the opening. Sadly, it should simplify into a tremendously boring endgame.

11. Bb5+ Nxb5 12. Qc6+

White gives this check before recapturing on b5 to (as we say in the technical language of chess) force the Black king onto a dorky square. The Black queen can’t interpose because then the rook on a8 would be hanging. I almost made a colossal blunder here – I had a recollection of White taking on d5 somewhere around here, giving Black an isolated pawn and exposing his king more. The idea is that Black still can’t take back with the queen for the same reason. But actually the queen can take back because it does defend the Ra8 from d5; and it also defends the Nb5, so White would have just been down a piece.

It’s good to check even when you think you know the book moves!

12...Ke7 13. Qxb5 Nxc3 14. bxc3

So Black didn’t let me take on d5. Still, I was pretty happy, as my c-pawn – though isolated – is passed, and my bishop gains another diagonal upon which it might check the Black king. In his notes to the stem game, Fischer-Euwe, Leipzig Olympiad 1960, Karsten Mueller attaches a ?! to 13...Nxc3, saying that the standard move now is 13...Qd7.

14...Rb8 15. Qa4

Now the White queen also gains new possibilities of troubling checks from the other side.

At this point, Black still had 44 of his 45 minutes left, and I had 19:24. After the game, Chris expressed surprise at my success, saying that Black is “just supposed to get a bad game after Qa4.” I looked the position up in my Caro book when I got home, and it didn’t mention 14...Rb8 at all – only Qd7 or Qd5. Furthermore, in my database where 724 games follow this line, 604 of those had Black playing an immediate 13...Qd7, and of the 86 that exchanged the knight on c3 first, 53 then played 14...Qd7 or 14...Qd5. Basically, with his exposed king, Black has to get the queens off quickly, or... stuff like this game will happen to him.

15...Qc7

I wasn’t expecting this move, either – only Qd7. I’m not sure what I should do then – if I exchange queens, then Black is just up a useful tempo on playing Qd7 on the previous move. Maybe this is what Chris was thinking of in his remark above.

Now it wasn’t clear how I should attack, and the potential fork on c3 is troubling, so I decided to castle and adjust my attack accordingly.

16. O-O f6

Now what I really want to do is (as they say in the chess literature) rip the pawns away from in front of his king. However, advancing my front f-pawn to f5 to provoke ...e5 is slow, and then when I play f2-f4 to rip it away, my own king is also exposed. So, I decide to provoke the e-pawn’s advance with my bishop, and then bring my front f-pawn against it.

17. Bf4 e5 18. Be3

Rybka likes my plan, which is especially encouraging as otherwise it keeps getting distracted by grabbing various pawns: my c- or h-pawn, or Black’s a-pawn.

18... Kf7

Rybka also endorses Black’s move, pointing out that if 18...Rb7 19. Rab1 Rxb1 20. Rxb1 Kf7 21. Qe4 Be7 22. Rb7 Qd6 23. Rxa7 and White is totally dominant.

Now... hmmm... I can grab a pawn or develop a rook to an open file while threatening to win the queen. What a difficult choice. NOT!

19. Rfd1 Rb7

So the rook ends up on b7 anyway...

20. f4

Up comes the f-pawn.

Rybka prefers a bunch of other lines where White just doubles rooks and Black grabs the c-pawn. But if you’re not a computer that never hangs material, it’s probably more productive to play to expose black’s king. Rybka calls the game about equal from about move 14 until Black’s 23rd, but (except for my Bf4-e3 maneuver) never seems particularly interested in playing it the way a human would.

And since it prefers its own lines by less than a tenth of a pawn, why bother paying attention to it?

20... Bd6 21. fxe5 Bxe5 22. Rd5 Re8

Rybka prefers 22... Bxh2+ (grabbing a pawn again!) 23. Kg2 Bd6 24. Rad1 Be7, giving black the whopping advantage of 0.16. However, it’s hard to believe that so passive – and yet so open – a black position can be good, and it’s hard to see what he can do against the advance of the c-pawn, which is bound to cause a lot of disruption when it arrives on c6.

What is perfectly clear, though, is that opposing rooks with 22...Rd8 loses. Tactical control!

After exchanging on d8, White has 24.Qc4+, and wherever the king goes, he will lose material: 24...Kg6 25.Qe4+, 24...Ke8 25.Qg8+, and if the king moves to a black square instead, Bc5+ forces him onto a white one.

23. Rad1 Re7?

After pushing the rook up a square, Black is lost. He had to try 23... Qc8 24. Rd7+ Re7 25. Rxb7 Rxb7

and now 26. Qe4 when White can play against the Black kingside or just push the c-pawn.

Rybka calls this equal again, but it’s hard for me to imagine Black surviving.
But not 26.c4?, when Black has 26...Qh3

Okay, back to the game: White now has two wins – one very, very simple and one complicated. And the move I played, which only wins if Black is not 2400 or above.

24. f4?!

This was my move. The simple win is 24. Bc5, when the Re7 can’t move off the second rank because of Rd7+. My only explanation is that I had looked at so many lines in which I play Rc5 or the pawn to c4-c5-c6, that moving the bishop there somehow fell outside my area of attention. It had somehow become a piece that supported those other ideas.

The complicated win is 24. Qg4, coming around the other side again. At first glance, the threat is merely to check at h5 and take Black’s h-pawn. But actually there’s also a threat of 25. Rc5 and Black’s queen is getting trapped: 25...Qb6 26.Rxe5, or 25...Qb8 26.Rc8 (supported by the Qg4).

24... Bxc3?

Black committed two important miscalculations in entering this position. After the game, he said that he should have just taken on e3 here, since he has some compensation for the queen. He had overlooked that I play (24...Rxe3) 25.Qc4+ and his queen goes for just the bishop.

But we were both so concerned with rescuing the bishop that we missed 24... Qxc3! (Rybka) here. After 25. R5d3 Rb4 26. Qa5 Qc4 27. Qc5 (27.fxe5 Qg4+) 27... Qxc5 28. Bxc5 Rxf4 29. Bxe7 Kxe7 30. Rd7+ Ke6 31. Rxg7 h5 32.Kg2 a5 it’s going to be very hard for White to make anything out of his nominal material advantage.

25. Rc5 Qb6?!

And again, correct is keeping the queens on with 25... Rb4 26. Qa3 Qb7 27. Rxc3 (Rybka) when White’s own exposed king and Black’s themes like Qf3, Rb2 again make White’s advantage merely nominal.

26. Qc4+

Chris’ crucial oversight was that after he interposes the queen here, I can exchange on e6 first and then take his bishop. He had only looked at me taking on c3 immediately, when he can play Qxe3+.

26...Qe6 27. Qxe6+ Rxe6 28. Rxc3 Rb2 29. Rd7+ Kg6 30. Rxa7

Here Chris had 32 minutes left, and I had 2:50. But with an increment (even a five-second one) this is a comfortable amount of time for such a position. The rest is included just because a few cute things happen.

30...Re2?!

Black can use the power of his two rooks in creating mating threats to win the a-pawn, which puts up more stubborn resistance: 30... Rd6 31. Bf2 Rd1+ 32. Kg2 Rdd2 33. Rf3 Rxa2. Black should still be lost here, I suppose; but it’s very technically difficult.

31. Bf2 R6e4 32. Rf3

Played with the express intention of supporting f4-f5+, although this isn’t very productive at the moment because White’s bishop doesn’t have access to e3. However, he gets distracted by the a-pawn...

32...Rc2 33. a4 Rcc4 34. a5 Ra4

35. f5+ Kh6 36. Be3+ Kh5 37. Rxg7

Ow. Black is almost mated. Luckily for him, he can exchange a pair of rooks.

37...Rg4+ 38. Rxg4 Kxg4

39. Rg3+

This is the sort of position where a GM would get embarrassed about missing the insta-win with 39. Rf4+ !

Rybka also points out 39. Kg2! with the idea of 39...Rxa5? 40. Rf4+ Kh5 41. Kg3 and White is making mating threats again. Me, I’m just happy that with one minute left on my clock I am about to achieve a position...

39... Kxf5 40.Bb6

where all my pieces are protected naturally, I can give a bunch of rook checks to pump my time up at will... this is how an ordinary person wins a won ending with just a minute left.

40...h5 41. Kf2 Kf4 42. Rf3+ Ke5 43. Re3+ Kd5 44. Kf3 Ra2 45. h4 Ra4 46. Rd3+ Kc6 47. Rd4 Ra3+ 48. Kf4 Ra1 49. Rc4+ Kb7 50. Rc7+ Kb8?!

This was really funny to me – in placing his king on the back rank, Black has come very close to achieving a thematic position from my game with Matt Bluestone; move the bishop and a-pawn one file to the right, and put my king at b6 and you have the exact “Bluestone position” (see the last diagram at the bottom of this page). So you know where my king was headed now.

After my next move, Black can snag my h-pawn with Ra4+xh4, but then after a5-a6 it’s hard to stop the mate on the back rank.

51. Rh7 Rf1+ 52. Ke4 Re1+ 53. Kd5 Re5+

Of course, after 54.Kd6 Black has no safe checks and a5-a6 (setting up a mate on the back rank) can’t be stopped, but I had a feelin’...

54. Kc6 Re6+ 55. Kd7 Re5 56. Bc7+ 1-0

So, I entered the last round on first board as the only 3-0, playing the only 2.5-.5 I think I actually had the toughest schedule -- Girardo and another guy I beat were playing on board two for third place. I lost on board one, but they drew on board 2, so I ended up in clear second with 3-1.

It's not just my first prize in a tournament since... 1986; it's actually the first time I haven't really embarrassed myself in a tournament in a long, long time. It feels good. :-)

Rudeness, randomness and tactics

2010-07-03T20:56:00.000-07:00

First, a brief quiz

You are to find the best line in each of the following positions. In each of them, there may be more than one line that gives an advantage, but you are to find the best one.

Black has just played Bc7xf4. All sorts of things are hanging. What’s White’s best line?

White to move again. Black would be a rook down after Bxf7, but if he hasn’t resigned yet, that’s not going to make him do so. Make him resign.

Black to move. This position is more complicated than the first two. :-) White threatens mate with 35.Ra7+ and 36.Qxh8.We have reached this position after the moves 32... Nf3+! 33.Rxf3 Rxg2+! 34.Kh1. Time to finish White off.

White has just played e5. What should Black do?

Rudeness in chess

I had a little talk with Todd recently about rudeness in chess – not verbal rudeness, but situations when one party plays on longer than they should. Perhaps it’s artificial to say that this isn’t verbal rudeness, because in Go (the Japanese board game) this is called “talking with your hands” – that is, your hands are saying is “I think you suck so bad that you can’t beat me even though I’m down a rook.”

But leaving that aside, I’ve started a new study program. I’m actually enjoying it a lot – there are a lot of neat tactics in even the simplest or most one-sided games, and I never really appreciated them back in the day, when I was much more busy beating myself up for not seeing them in the game.

And seeing the tactics is of course the critical factor in whether to resign – are you seeing them; is your opponent seeing them, or does it seem like you can swindle him?

I remember one Continental tournament where John Donaldson was doing that thing where the famous player is manning a room with a demo board and anyone can bring in their games. One of the A-players brought in a game, and Donaldson starting off by praising them for following cutting-edge theory. Then of course one of them deviated and he said “No, you can’t do that” but of course the other player didn’t find the refutation. Donaldson’s cries of “NO!” grew longer and more heartfelt as the game went on, and at one point he dropped his face into his hands, then straightened up and turned to the audience: “I am now officially telling all of you NEVER to resign a game in one of these sections unless you are faced with mate on the move!”

We’ve all been on both sides of this, of course – more often in blitz, but sometimes in slow games. I’ve found a couple of games of my own that are relevant to this theme. But first an answer to our quiz:

The point of showing these positions is to highlight how much aggravation you can save yourself with some tactical precision.

White can win the exchange back by 1.Nxh6+ Bxh6, but then it’s not clear he has a workable advantage at all – the isolated e-pawn may outweigh the two bishops. White can go up a piece with 1.Ne7+ Kh8 2.Nxc8 Bxh7+ 3.Kf1 Ne6 4.Qc2/c3 Bg3 with ideas of Qf4+, Rh1+ and so on. This gets complicated and White is under a lot of pressure. White can make it even more double-edged with 4.Qe7 Bxh2+ 5.Kf1 Qxc8 6.Qxf7 Rh4! but like I said this is complicated.

By the way, White has to take on c8 with the knight if he wants to keep the extra piece: 1.Ne7+ Kh8 2.Qxc8 Qa7+ wins the knight back, as 3.Qc5?? Be3+ is suboptimal.

So especially if White is tired, the best line here is not to bother with the exchange but to cut straight to the chase with 1.Ne7+ Kh8 2.Ng6+! hxg6 3.Qf8+ Kh7 4.Qxg7#. I think that this line is a little harder to spot than usual here, because White might have started out trying to decide what’s the best way to win back the exchange, and once you’ve looked at Ne7+ with the idea of Q/Nxc8, it’s a little harder to then think of it moving in the opposite direction to g6. But it's hard to keep your head and notice lines like this when there's a lot of other stuff going on.

The other quiz positions come from two games of mine, and will be discussed when they arise in the games below:

Shernoff - Richard Lewis Mid-West Amateur Team Championships, 2003 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.f4 e6 7.Qf3 Bd7 8.e5

This is the last quiz position (above).

We were both under the impression that I was winning material here, but this is not the case: 8...Nc6! at least equalizes, because of the hanging Nd4. Suddenly it is White who risks losing material or just getting the worse position. However, Black played a more natural move.
8...Bc6?? 9.Nxc6 Nxc6 10.exf6 Qxf6 11.Bd3 Qd8

Apparently Black was afraid of 11...Be7 12.Ne4

12.0-0 Be7 13.Bd2 Qd7 14.Ne4

I'm preparing to use my pawns to restrain and then chip away at his compensating pawn center

14...h6 15.c4 0-0-0 16.Bc3 f6 17.b4 Na7 18.a4 Rdf8 19.b5 Kd8 20.Rad1 Ke8 21.Nc5 Qc8 22.Bg6+ Rf7 23.Nxb7

Here, I was expecting 23...Qxc4, giving us one of the positions from our quiz:

During the game I was planning 24.Na5 Qc7 25.Qa8+ Nc8 26.Rc1; however, this is inaccurate.

In Go, there’s a concept that gets translated as “inducing move.” You want to make a move for reasons of your own, so you play an otherwise meaningless move that sets the enemy in motion in that direction. Then you play the move you wanted originally, which now has its original purpose plus it stuffs the new motion of the enemy.

Here, White can win a pawn with 24.Rxd6, since 24...Bxd6 is met by a recapture that forks the queen. But 24.Rxd6 itself carries no threat, so Black can just castle and White has only won a pawn. (Well, he can’t castle in the game, but he can if it’s just a quiz position!)

However, after 24.b6! Nc6 25.Rxd6! white captures with tempo, because he’s attacking the knight. Then 25...Nb8 26.Rd8+ forces the knight fork on d6. If Black replies to 24.b6! with 24...Nc8, then 25.Rd4 and (in any order) Rb4 when the queen goes to b3, Be4 when the queen goes to d5, and Ra1 when the queen goes to a2 will trap it.

Back to the actual game:

23... Qb8

24.Rfe1

Fritz wants 24.f5 e5 25.Qd5 Rhf8 26.c5, thus showing that a chess program can be sadistic, but equally good by this point is 26.Nxd6+ Bxd6 27.Qe6+ with mate on d7. However, I didn’t want to just threaten to put a pawn at e6, I wanted to force the pawn there.

24...d5 25.cxd5! Qxb7 26.dxe6

At the post-mortem, my opponent, who was about 10 and very polite and respectful, asked whether at what point it might have been rude of him to continue playing. I suggested that once variations like the one here: 26...Qxf3 27.exf7+ Kf8 28.Rd8+ Bxd8 29.Re8# start appearing, one should either allow them or resign. On the other hand, the position is not exactly annoying for White to play, so the rudeness is minor...

And it also shows that black is not the only one who can be obnoxious by playing on here: after White does the big sacrificial windup for his Morphy-style mate: 26...Qxf3 27.exf7+ Kf8 28.Rd8+ Bxd8

He doesn’t have to actually deliver it: after 29.gxf3 Be7 30.Bb4 Nc8 31.b6 followed by 32.b7 and now White is the one who’s being a jackass by continuing to play. Well, back to the game:

26...Qc7 27.Rd7

Here again Fritz saw a quicker mate with 27.exf7+ Kf8 28.Rxe7! but the one that’s coming will be good enough.

27...Qb8 28.Qd5 axb5 29.exf7+ Kf8 30.Rd8+ 1-0

What surprised me when I pulled the game was how much substantive tactics were in it even though from a competitive standpoint the game is completely trivial. However, in a less crushing position my planned inaccuracy at move 24 might have been enough to let Black back into the game. Likewise the 8...Nc6 shot is well worth spotting, before I give someone else that chance (or someone gives me the opportunity). And then there were the cute politeness “twin” variations at move 26.

The next game, however, is meatier.

Shernoff (2110) - Matthew Bluestone (2160) Ft. Wayne, 1996

This was the most unfortunately memorable tournament location in my experience. Bill Goichberg was experimenting with trying to run Continental tournaments in new locations, and a bunch of us from the University of Chicago chess team tried to help him out by driving down to Fort Wayne. The hotel had a strange landscape in back of it – almost an acre of flat blacktop expanse, with an incredible array of fast-food restaurants sprouting out of it like mushrooms. There were no street or lane markings (or even parking spaces) – just pristine blacktop and fast food.

I went downstairs the first morning and asked the manager if there was someplace cheap nearby that we could eat breakfast. Obviously the blacktop expanse was available but I try to avoid that kind of stuff. The manager said that there was just the hotel restaurant. I said yeah, but these are undergraduates, so I’d like to find someplace cheaper. He said, “There isn’t any.” I said “Not in the whole city of Fort Wayne?” “That’s right.” We ended up at a subway about half a block from the hotel.

The hotel also featured a maid who loudly demanded that we pay her to clean our room, because it was so messy. I just exchanged a stack of towels with her. I considered complaining about this, but then reflected that this would be to the manager who had just insisted that there was no other place to eat in the entire city.
And during the tournament, a very nice sweater disappeared from my hotel room. I am not surprised that Bill did not return to this venue.

My opponent in this game, Mathew Bluestone, was a top college player who was on the Harvard team. Yes, this was back when

a) being rated 2160 made you a top college player, not an above-average high school player
b) such a rating could get you a chess scholarship
c) the only schools recruiting chess players were Ivies
d) you only got a (full or partial) scholarship, not a free ride, a stipend, and a bogus “assistantship” lecturing B-players on the alternatives on move 20 of the English attack in the Najdorf variation
e) you were expected to actually take your classes.

Truly simpler, more innocent days. Our game, however, was neither simple nor innocent.

1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 d6 6.g3 a6 7.Bg2 Nbd7 8.0–0 Qc7 9.Be3 Rb8 10.a4 b6 11.Qe2 Bb7 12.Rae1 Be7

13.Nd5?

Contrary to my earlier experience, this is not always a good move. Here, White should just play f4 and look for play with f5 or g4-g5, now that Black’s king can’t castle queenside. 13.f4 Nc6 can be met simply with 14.Bc1, and now White is threatening 15.b4 Ncd7 16.Bb2, improving the position of his pieces and gaining space.

13...exd5 14.Nf5 dxe4 15.Nxg7+ Kd8 16.Nf5 Ne5

I don’t know about you, but I think that Black has a fantastic position!

17.Bf4?!

I made a long analysis after the game to show that this move is much stronger if my Re1 is on the d-file instead (duh!), but the Re1 actually does a good job of inhibiting ...Nf3+, which I think (in retrospect) Black must have been trying to arrange. Bf4 is still pretty clueless – the bishop should go to g5 right away. And I disagree with both of Black’s pushes of his h-pawn that follow – he should have played a rook to the g-file instead.

17...Qd7 18.Nxe7 Qxe7 19.Bg5 h6?! 20.Bh4 Kc7 21.Qd2 Rbe8 22.Qd4 Qe6 23.Re3

23...Nfd7

Better is Ng6. But now my Bh4 isn’t doing much, so I relocate it to g3.

This game is sort of a weird twin of the first one. Here I’m the one who lost a piece in the opening for no particular reason; however, as in the previous game, Black has met the situation by walking his king around and shuffling his other pieces (maybe he was hoping that I would make another ridiculous sac?) and the tempi he’s wasted enable me to mount a genuine attack. Already (compared to the previous diagram, it’s looking more like I really intended for all this to happen, and in the next diagram it’ll look even better for White (even though by then, ironically, Black has a forced win).

24.g4 Nxg4 25.Rb3 Bd5?! 26.c4 Bc6 27.Bg3 h5?! 28.a5 Rb8 29.axb6+ Kb7 30.Bxd6 Rbg8 31.Ra1 Nge5

So by now the position really does look like White is attacking (my bishop certainly looks a lot better on d6 than it would on h4), but in the meantime I’ve finally chased a black rook to the g-file. So both of Black’s dearest wishes will come true in the next move-pair: I will make another wild sac, and Black will get to play Nf3+.

32.Rxa6 Nf3+

On 32...Kxa6 I was planning 33.Ra3+ Kb7 34.Ra7+ Kc8 35.Rc7+ Kd8 36.Bxe5, which may not be sufficient, but is more than I had any right to hope for after my foolish 13th move. One entertaining continuation is 36...e3 37.Bf6+ Qxf6 38.Rxd7+ Ke8 39.Qxf6 Rxg2+ 40.Kf1 Rxf2+ 41.Qxf2 exf2 42.Rc7 Bd7 43.b7 Ke7 44.c5 and White should do well by pushing those queenside pawns.

33.Rxf3

If the game hadn’t been so eventful already, I might have been tempted to let the queen go here with 33.Kh1. This works out well (and humorously) if Black decides to just go straight for the mate with 33...Qh3.

Things look dire for white, as 34.Bxh3 Rg1# and 34.Bxf3 Qf1# are sub-optimal, and the Bg2 can’t be defended. However, after 34.Ra7+ Kc8 35.b7+ Bxb7 36.Ra8+ Bxa8 37.Rb8+ Nxb8 the queen can now be taken with check: 38.Bxh3+! Nd7 39.Qc5+ with a quick mate. Note the power of the two bishops! ;-)

But unfortunately if Black just takes the queen, White’s ball of pieces on the queenside loses all cohesion and he has no effective follow-up, for example: 33.Kh1 Nxd4 34.Ra7+ Kc8 35.b7+ Bxb7 36.Rbxb7 Qxd6. Luckily I avoided all this temptation, as I hadn’t seen the check at all, and was so grateful to notice my rook covering that square that I just snapped it off!

33...Rxg2+?!

Far be it from me to criticize a flashy move that could have led to a forced checkmate, but it is simpler to just recapture: 33...exf3 34.Ra7+ Kc8 35.Rc7+ Kd8 36.Bg3 fxg2 37.Bh4+ f6 38.Bxf6+ Ke8 when White's checks come to an end and Qe1# is threatened.

34.Kh1?

Strangely, this is a mistake.

Giving us our third quiz position.

I can’t capture the rook: after 34.Kxg2? exf3+ 35.Kf1 Qe2+ mates on the back rank, and 35.Kg3 Rg8+ is too gruesome to contemplate. But the king should have gone to f1 instead. Supposedly, Michael Stean once said “If you have only one move that doesn’t lose instantly, there’s no excuse for not finding it!” The trick is to know when you only have one move.

Black proceeded optimally for a while:

34...Rhg8 35.Ra7+ Kc8 36.Rc7+ Kd8 37.Rg3

But now he missed 37...Qh3!!, forcing checkmate. This is why the king should have gone to f1 instead of h1. Then Black would have been legitimately over-extended. But this Qh3 shot is one of those moves that’s not terribly difficult to find when you’re given a quiz position and told that Black has a forced mate. In the game, after all the confusion that has come before, it’s hard to keep a clear head and notice the possibility.

37...R2xg3? 38.fxg3 Qh3 39.Qd1?!

Better was the self-defence with 39.Kg1, after which my Fritz of the time put White up almost three pawns, which is pretty amazing considering the actual material situation.

39...Ba8?

More in the spirit of the game (true, by now Black was probably pretty sick of the spirit of the game) would be 39...Ba4!, with the idea of 40.Qe1 Nxb6, although after 41.Rxf7 the mate on f1 is covered and White’s queen is free to roam again. But it once again becomes a difficult game.

There is a clear win here for White, but (as with 37...Qh3!!) it requires extraordinary tactical precision and a clear head, which pretty much guarantees that we wouldn’t have found it in the game.

First White has to realize he can save the b-pawn with (39...Ba4!) 40.b7! and the threat of 41.Rc8# doesn’t give Black time to take the queen. Then Black plays 40...Nb8!

and now after 41.Qe1 Bc6 Black has disturbing counterplay. So White has to win the bishop with 41.Rc8+ Kd7 42.Qxa4+

And now we’re at the third crossroads. There’s mate hanging on f1, and White’s instinct to always go forward when attacking the king may get him into trouble. He may even forget about Black’s knight and hang his queen after something like 42...Ke6 43.Re8+ Kf5 44.Qd7+?? (skewering the black queen!) or 43...Kxd6 44.Qa6+??

Here White has to see that moving the queen back to where it was before is good: simply 42...Ke6 43.Qd1 or 42...Kxd6 43.Qd1+ Ke7 44.Rxg8 are dead won for White.

Even Fritz showed more sense here, suggesting 39...h4!, with the idea of 40.Rxc6 hxg3 41.Qe2 and the position is still complicated.

By the way, it does look like we were in a wee bit of time pressure here coming up to move 40, and our tactikular precision suffered a mite because of it. But actually the first time control was at move 30, and Matt’s brain was just melting from all the crap we’d been through. But now I shut him down smoothly after

39...Ba8? 40.b7 Bxb7 41.Rxb7 Rg6 42.Bf4 Ke8 43.Rb5 h4 44.Rh5 Qe6 45.Qd5 hxg3

46.hxg3!?

It hardly matters that I missed a quick mate here with 46.Qa8+ Ke7 47.Bc7. A Tal or Shabalov may have been happy and proud to go for a continuation like 47...g2+ 48.Kg1 Qxc4 49.Qd8+ Ke6 50.Qe8+ Kf6 51.Be5+, but I was playing on a “no further craziness allowed” imperative. I realize that this sort of contradicts one of the themes of the post – that one should try to be super-precise and finish off the opponent quickly so as to avoid screwing up later. But, tired from all that has come before, there’s actually a lot more chance of me screwing up a line like this than in playing a simple endgame where I have a clear advantage.

Though I have to add that I pretty much saw the continuation up to the next diagram at this point, where it’s a lot simpler position, and this tips the balance. If queens were going to stay on with my king so open, then it would have been better to look for the quick mate.

46...Qxd5 47.Rxd5 Rb6 48.c5 Rxb2 49.c6 Nb6 50.c7 Rc2 51.Rd8+ Ke7 52.Rb8 e3

53.Bxe3!? Rxc7 54.Rxb6

In objective chess terms, 53.Rxb6 e2 54.Rb1 was better, but I just didn't want to bother thinking any more. And that line does leave open the option of me trying to approach the pawn with 55.Kg2?? d1/Q+. :-)

Note that I did NOT say that this line would have “speeded up the game.” Given my opponent’s behavior from here on, that might have been true in terms of number of moves, but not in terms of hours out of my life. This brings us back to the rudeness theme.

Bluestone had used up all of the first time control a long time ago, and (in playing the game out) sat very deliberately and used all his time for the sudden death control also, making the game last well past the starting time for the next round. In fact, he offered me a draw later on when I repeated moves (I said “No thank you.”).

I suppose he wasn’t just trying to be obnoxious, because my score sheet shows that I repeated moves a little bit further on (I needed a lot of calming down after that middlegame, and was proceeding along the lines of “do not hurry”) and he didn’t offer a draw again. He can’t have been hoping I would make another random sacrifice because, sadly, he doesn’t have anything left that I can sac for. But he didn’t resign until after (note the move number)

No question about White making progress!

80.Kg6 Rc6+ 81.Bf6 Rc8 82.Rh7 1-0

with about thirty people watching in a circle around us, including the TD tapping his pen on a scorepad.

Here’s one last thought about people who get upset with you because they’re insulted that you played “garbage” (or “not real chess”) against them: the result doesn’t matter. If you lose, they will be insufferably self-righteous and lecture you on the proper understanding of the game, and if you win they will be furious because you must have cheapoed them somewhere and destroyed the logic and beauty of them winning to show you how stupid you are.

I’ve been on both sides of that one, too.

Darga-Spassky, part 2 (the most beautiful bishop ending in the world)

2010-05-15T20:43:00.000-07:00

This continues the game Darga-Spassky, Round 1 of the Amsterdam Interzonal, 1964. The first 92 moves of the game (!) are in a separate post, Darga-Spassky, part 1. This post attempts to solve the resulting bishop ending at move 92, given best play.

This ending (or at least my posting of it) has a story behind it. When I was playing through these interzonal games, I stopped and wondered why Spassky didn’t play 92...Bc2 instead of his obviously silly blunder. At first, I couldn’t find a way for White to win if Black just kept shuffling his bishop between c2 and d1. I spent some time looking at it and found a win that I thought was really beautiful. I was very enthused.

Okay, time passed. I hadn’t played or looked at chess for a while. I had a pair of chess friends visiting from out of town and I thought it would be cool to pull out this ending. To my horror, I found that I hadn’t written down the winning method. I spent some time that afternoon trying to reconstruct it, but to no avail. Well, no biggie, I thought: my friends are both strong players so we’ll just figure it out together over dinner. To my surprise, we were unable to do so. The bishops danced and danced, but zugzwang was elusive and no other winning method presented itself. A couple of weeks later, I closeted myself with the ending for the weekend and eventually figured it out. So here it is. I hope you enjoy it.

If Black plays the best defence,

92...Bc2

Then the critical position arises after the forced exchange of d-pawn for g-pawn:

93.Bd5 Kd7

If Black tries to hold the g-pawn, he immediately gets into zugzwang: 93...Bd1? 94.Bf7 Bh5 95.Ka4 Kd7 96.Kb5 Kxd6 97.Kb6 Ke7 98.Bg8 Kd6 99.Bh7. I’m pretty sure that this was the line that so impressed me with its beauty back when; now it seems a bit callow.

94.Bf7 Kxd6

Black should just take the d-pawn and leave his bishop on c2. As in the game, if he tries to attach the bishop to the c-pawn, he just loses more quickly: 94...Bd3 95.Kb3 Kxd6 96.Bxg6 Ke7 97.Bh5! Bf1 98.Bf3 Bd3 99.Bd5 and Ka4-a5

95.Bxg6

White has "two weaknesses" to play with. One is the f-pawn, and the other is the possibility of king penetration with Ka4 (which I suppose boils down to the weakness of the c-pawn).
White's aim is to produce a position where he is attacking the f-pawn while only Black's bishop is defending it; then Kb2 will force the bishop to choose between abandoning the f-pawn or allowing Kb3-a4, so here for instance 95...Ke7? 96.Kb2 Bd3 97.Kb3 +- as above.

95...Ke6! 96.Bh5!

In a simpler world, White would be able to play 96.Bh7, which forces Black's king to move away from the f-pawn and allows White to complete his strategy. Unfortunately, after 96...Kf7 97.Kb2 Bd3 98.Kb3 Kg7 the bishop runs into a bit of trouble, and the position becomes equal. 96.Bh5 also restricts Black’s bishop.

96...Ke7 97.Bf3

so white has to attack the f-pawn from the other side, where he has a longer diagonal. If you put the white bishop on c8 here, you see that White has an immediate win on the next move with Kb2. To prevent this, Black would have to commit all his resources immediately: 97...Kd7 98.Bb7 Bd1 (to meet 99.Bc8+ Kxc8 100.g6 with 100...Bh5 101.g7 Bf7) but this loses to 99.Ba6 and now Black can’t move his bishop, or move his king away from c8; so we get 99...Kd8 100.Bb5 Ke7 101.Ba4 B moves, 102.Bc2 and Ka4.

So Black’s best defence is to bring the K around to the other side of the pawn:

97...Kf7 98.Bb7 Kg6! 99.Bc8 Bd1 100.Bd7 Bc2 101.Be8+ Kg7

and here White has three tries:

A) 102.Bh5 Kh7 and White makes no progress

B) 102.Ka2 Bd1 103.Kb2 Bf3 (or Kh7) 104.Bd7 Kg6 and again White must reset the diagram position with 105.Ka3 Bd1 106.Be8+

and the winning line:

102.Ba4! Be4
103.Bd7 Bc2
104.Kb2

Bingo. Mednis would be proud.

Depending on how many steps Black's king took to reach g7, this position can also be reached with Black's bishop on d1. Then white wins as in the 97...Kd7 variation after 102.Ba4 B moves 103.Bc2 and Ka4.

So what do you think? Is it beautiful? Nice? Just another bishop ending? Is it worth falling on your sword to avoid all of this? Spassky had a slow start to the tournament, and not just because he lost this: his other early-round games didn't go so well, either. Maybe it had something to do with spending all his rest days sitting with Darga pushing the bishops around for another few hours.

Here's how the actual game went, from the starting point of this post:

92...Be2?
93.Ka4 Bxc4
94.Ka5 Be2
95.Bb5 c4
96.Ba4

Just a little fancy. The more natural line would be 96.Kb4 c3 97.Ba4

1-0

I wonder how long it would take a strong computer to find the win after 92...Bc2. They don’t have the concepts of “White wins if the king passes a4” or “the bishop needs to come around to the longer diagonal” so its search would be tremendously less efficient, and it might originally reject the whole concept of Bxg6/...Kxd6 as exchanging a pair of pawns while Black’s king comes out of the box. Though of course after a few billion bishop and king shuffles I’m sure it would converge on a solution.

Darga-Spassky, part 1

2010-05-15T19:42:00.000-07:00

This game is the intersection of a couple of interests for me. First of all, I’ve found that when top-notch players lose, the game is usually something special. In this case that is very true, although sometimes it’s “special” as in “cool” and sometimes “special” as in Special Olympics. The other interest at the time was self-improvement: I had decided to play through all the games of an interzonal, to see how some top-notch players played against each other and against people who weren’t quite so good.

Darga - Spassky Amsterdam IZ, 1964

1.Nf3 Nf6 2.c4 e6 3.g3 b6
Spassky playing the QID? It soon becomes clear that this is not a good choice.
4.Bg2 Bb7 5.0-0 Be7 6.Nc3 0-0 7.d4 Bb4?!
Losing a tempo in order to give up the two bishops when your position is already really passive is not a good idea.
8.Qb3 Bxc3 9.Qxc3 d6 10.b3 Nbd7 11.Bb2 Re8 12.Rad1 Rc8 13.Rfe1?! Qe7 14.d5 e5 15.Nh4

Black's position is looking more and more like one of those textbook passive/inferior positions that will soon be wrecked by some attractive sacrifices. Put white’s rook back on f1 and use that tempo to play f4 and it becomes even clearer.

15...Nc5 16.f4 Nfd7 17.e3 a5 18.Qc2?!

Darga doesn't lose his advantage this way, but he shouldn't be pretending Black's queenside "play" amounts to anything. He has a huge space advantage and the two bishops, and he should be concentrating on a way to kill Spassky's king.

18...f6 19.a3 Ra8 20.Bc3 Qf7 21.Rf1

21...exf4 22.exf4?

I think this is where Darga starts to go really wrong. As played the rooks will just get exchanged on the e-file, instead of White being able to place them behind a pawn-storm. The crowd wants 22.Rxf4 when Black can't take the e-pawn because of 22...Rxe3 23.Nf5 Ree8 24.Rg4, threatening both Rxg7 and Nh6+

22...a4?!

The knight is just out of play on b3

23.b4 Nb3 24.Nf5 Nf8

25.Nd4?

Just leave the Nb3 alone! White should play something like 25.Kh1 and Rg1, Be4, g4-g5. To me, this is just the quintessential Soviet game. Throughout it, Darga seems to have the philosophy of just playing solidly, doing nothing the least bit interesting, and letting Spassky hang himself. Well, it eventually works, but the whole process would have been less painful for everyone if he’d just played real chess for more than one brief phase of the game.

25...Nxd4 26.Bxd4 Qg6

Another reason to have kept a knight on f5. I'm sure that Edmar Mednis would be thrilled beyond words to exchange queens with the two bishops in hand, but 99% of all other chess players would have wanted White's huge space plus to amount to something more substantial.

27.Qxg6 hxg6 28.Rfe1 Kf7 29.Kf2 Ba6 30.Bf1 f5?!

Now Black's king is tied down to the weakness at g7, and his bishop is worse.

31.Rxe8 Rxe8 32.Re1 Rd8 33.Bd3 Nd7 34.b5 Bb7 35.Bc2 Nc5 36.h4 Nb3

The same mistake twice!

37.Bc3 Bc8 38.Re3 Bd7 39.Re1 Rg8 40.Re3

It's hard to tell whether white is in time trouble and just wants to make the time control before doing anything, or is just dicking around to make the point that he can. Judging by his play later in the game, it's the latter.

40...Nc5 41.Bd4 Ra8 42.Ke1

42...Ne4 43.Bd1

Spassky is willing to give up a pawn immediately just to get opposite colored bishops, and indeed 43.Bxe4 fxe4 44.Rxe4 Re8 45.Rxe8 Bxe8 46.Kd2 Bd7 47.Kc3 Bg4 48.Kb4 Be2 is a clear draw

43...Re8 44.Bxa4

Darga, for his part, is willing to trade a good pawn for a lousy one in order to get the rooks off

44...Nxg3 45.Rxe8 Bxe8 46.Bc2 Nh5 47.Be3 Ke7

48.a4

Now Darga plays very energetically, precisely and resolutely for the only time in the entire game, and acquires a winning advantage. Edmar Mednis would faint for joy over his play over the next 17 moves.

48...Kd7 49.a5 bxa5 50.Kd2 Ng3 51.Kc3 g5! 52.hxg5 Bh5 53.Kb3 Be2 54.Bd2 a4+ 55.Kb4 a3 56.Bb3 Ne4 57.Be3 g6 58.Kxa3 Nc5 59.Bxc5! dxc5 60.Ka4 Bd3 61.Ka5

White will spend the rest of the game trying to achieve this sort of breakthrough again.

61...Be2 62.b6! cxb6+ 63.Kxb6 Kd6 64.Kb7 Bd3 65.Kc8 Be2

White now has a fairly standard win by walking his king over to f6, forcing Bh5. Then Black has to move his king, and (after Ba4-b5) White will be able to play Ke5, d5-d6, Kd5 and take the c-pawn (or just queen the d-pawn if Black puts his king on b6).

I'm wrong here -- as Todd Rowland points out in his comment below, Black has a stalemate cheapo: 66.Kd8? Bxc4! 67.Bxc4 stalemate. So Black has an unusual sort of "blockade" along the back rank, and the position must be drawn because the White king has no route into the Black position.

66.Kb7?? And all these question marks are undeserved... :-)

However, Darga, under some sort of hallucination, now painstakingly negates all his previous progress. This is the sort of continuation that gives rise to those stories of Soviet collaboration...

66...Bd3 67.Ka6?? Bf1 68.Ka5?? Bd3 69.Ka4?? Bf1 70.Ka3?? Be2 71.Kb2?? Ke7 72.Kc3 Kd6 73.Bc2 Ke7 74.Bd3 Yeah, that's going to work 74...Bd1 75.Kd2 Bb3 76.Be2 Kd6 77.Kc3 Ba4 78.Bd3 Bd1

At this point, both players seem to feel that all black needs to draw is to keep his bishop on this diagonal to keep the White king out -- counterattacking the c4 pawn if necessary.

79.Kd2 Bb3 80.Kc1 Ke7 81.Kb2 Bd1 82.Bc2 Be2 83.Kc3 Kd6 84.Ba4 Ke7 85.Bb5

85...Kd8 ?!? ?? And this is just a losing move.

At first, I thought that this gives White some chances he doesn't deserve, after Black has clearly demonstrated that he knows how to draw. But perhaps White can just place his bishop on b3 and walk his king up the board anyway, decoying the Black king if necessary by pushing the d-pawn.

This shows a big difference between chess then and modern chess with sudden death time controls. Both players (being much stronger than me and seeing the stalemate defence) must have realized that the position was a dead draw, for the reasons mentioned above. However, Darga was able to exercise his privilege of playing on and on and on, and eventually Spassky either lost concentration, had a mad impulse, or committed a fingerfehler... we'll never know. In a modern situation, Black could have pointed out that White isn't really trying to make progress and had the game called a draw that way -- and White wouldn't have been able to continue without risk, since he would also been in danger of losing on time.

Perhaps one day we'll consider the adjournment era as backwards as the pre-clock 1800s, where the slower players used to consider for hours over one move.

86.d6!?

This rules out the win just mentioned, because of the vulnerability of White's d-pawn. So now the win is very complicated. On the other hand, if the win in the last note doesn’t work, then this is White's only winning try and Black blew it on the previous move.

86.d6 Bf3 87.Kb3 Bd1+ 88.Ka3 Bc2 89.Bc6 Bd1 90.Ba4 Be2 91.Bb5 Bd1 92.Bc6

At this point, Spassky played 92...Be2? and resigned four moves later. However, he can continue his previous policy of king-containment with 92...Bc2, reaching the critical position for this ending. That position is the starting point for the second post in this series, Darga-Spassky, part 2 (the most beautiful bishop ending in the world)

Sometimes tournament chess is like getting hit upside the head with a huge fish

2009-11-20T22:54:00.000-08:00

Those people who don’t play our royal game often imagine chess to be this detached, cerebral exercise. (Cue fiendish laughter here) For the last couple months, I’ve been getting settled in at my new job with Wolfram Research which has been great but has also left me with very few spare brain cells for appreciating chess. Which has meant that – through absolutely no fault of my own – in the few spare moments when I’ve tried to get this blog going again, my taste in games has gravitated towards games that are the Caissic analog of a roadrunner cartoon.

Case in point:
Victor Chubakov-Leon Shernoff Maroon Kings Tournament, University of Chicago, 2002

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. e4

The Geller Gambit (or Tolush-Geller Gambit), a sharp continuation that is considered unsound at the GM level, but not below. On the one hand, I’ve seen games where the young Kasparov lost as White; on the other hand, I was present at a tournament where perpetual “could be IM if I felt like it” David Gliksman used it (as white) to crush Igor Ivanov, who then immediately used it himself (even though of course it’s completely not in Ivanov’s style) to crush another IM in the last round. (Gliksman, if I remember correctly, drew with Michael Brooks in about 7 moves to share first place between them)

I used to play a gimmicky continuation invented by Smyslov, but gave it up because of bad results, even though I always got good positions. Also because I realized it was just unsound in one game (confirmed by John Donaldson in the post mortem), even though my opponent didn’t see it in the game.

5... b5 6. e5 Nd5 7. a4 e6

The main line. The other major continuation is 7...h6. Also possible is 7...Qa5 (according to my book, anyway) and 7...Be6 (Smyslov's continuation), with the idea of Nxc3, Bd5, and e6.

8. axb5 Nxc3 9. bxc3 cxb5 10. Ng5 Bb7 11. Qh5 Qd7

Okay, this is also a legitimate way to reach the main line (11...g6), but also a gimmicky sideline in its own right. White can't take 12.Nxh7 because after 12...Nc6 Black threatens sacrifices on d4. You’ll get the idea of what happens then from what happens here.

12. Be2 Bxg2 ??

Based on the results of this game, I have to say that this move is just losing, even though it had been played at the GM level before (and possibly since).

Black should just play 12...g6 to enter the main line. He then plays Be7 and goes for the setup with Bd5 and Nc6. I, however, had memories of Black grabbing this pawn thus keeping White's king in the center (see Kievelitz-Crouch, Decin 1996 at the end of this post), so I got over-ambitious.

Though, to be honest, I had another problem with the main line, in that book (at this point in time) had White able to force a repetition with stuff like 12...g6 13.Qh4 Be7 14.Qh6 Bf8 (if Black can’t castle, he’s doomed) 14.Qh4 Be7 (see previous comment) 15.Qh6, etc. I don’t know whether this assessment has changed in the meantime. But it seems like an attractive line for a lower-rated player, as Black either has to allow this draw or play one of these cheesy sidelines that subject him to a ferocious attack.

13. Rg1

13...Bb7!?

Afterwards, I thought that better would be 13...Bd5, as in Kievelitz-Crouch. However, I was still hoping to get my Nxd4 sac in, so I left the d-file open. And in fact, Couch should have been vulnerable to the exact sort of continuation that I was here, but he wouldn’t have had the open d-file for counterplay (such as it is).

14. Nxh7 Nc6 15. Nf6+ gxf6 16. Qxh8 Nxd4!?

Quiz question #1: What is White’s best response to this move? Hint: there is a very, very, very clear answer. To help you avoid peeking, I will babble on for a little while to fill up the page.

My thought at the time was that objectively Black's just losing here, so he has to start the complications right away. 16...0-0-0 just hands Victor the correct line: 17.Rg8, and now if Black starts the same sort of fun with 17...Nxd4 18.cd Qxd4, White is always a capture ahead of him after, say, 19.Rxf8 Qxa1 20.Rxd8+ Kc7 21.Rd1

After the game, I said to Victor that this was similar to last year's game, in that after a certain point we entered a tactical flurry, and I prevailed in the period of mutual oversights. The interesting thing about this year's game is that neither of us realized how early that period began.

Okay, if you’re still looking for a hint, I’ll tell you that the most important feature of Black’s last move is that it gives up control of the b4 square, which means that black can’t push his b-pawn if he needs to.

Here, Victor can win with 17.Qxf8! Kxf8 18.Ba3+, giving Black the lovely choice between 18...Ke8 19.Rg8# and 18...Qe7 19.Bxe7+ Kxe7 20.cxd4, capturing the knight under, ummm, superior conditions.

Is the roadrunner theme becoming clear to you yet?

So objectively, Black should have castled last move, even though it sucks. I think you’ll agree with me that the pawn grab Bxg2 was bad, in that Black’s two moves ...Bxg2 and ...B retreats are worth a lot less than White’s corresponding moves Rg1 and Rg8. So better, actually, to castle on move 12 instead of grabbing the g-pawn. But then White‘s king wouldn‘t be trapped in the center and Black would have little play. Best not to enter this line at all.

Victor was also (unbeknownst to me) starting to hallucinate, in that he rejected 17.Rg8 because of 17...Nc2+ 18.Kf1 Nxa1 19.Rxf8+ Ke7

because he "didn't see a mate" and didn't want to be "only up a piece" after taking twice on a8. After the game, we agreed that just being up the piece was good, but there are also at least three quick mates in the position! See if you can find them! The answer is at the end of the post, as “Mate cluster #2”.

I, of course, was going to castle on move 17, entering the "correct line" that I didn't want him to find (above).

The game continued:

17. cxd4?? Qxd4 18. Rb1?

Again, there's another long mate after the thematic 18.Rg8 Qxa1 19.Rxf8+ Ke7

and 20.Rxf7+. I’ll let you find it on your own, and I’ll put the answer at the end of the post. It’s not easy to visualize all the way to the end. Objectively, it looks like the passive move in the game blows White's advantage. Which means that if it takes so many ?? moves for White to not be winning then ...Bxg2 probably deserves something like four or five question marks instead of two.

18... O-O-O

19. Rg8??

At this point, White has to come back and defend against Qc3+ with Qh3 or Rg3. Fritz’s reasoning for declaring the position almost equal then seems to have been something like 19.Qh3 Qxe5, but I tend to distrust grabbing pawns as compensation for a whole rook. Ramming the c-(and b-?)pawn(s) down the board looks more appropriate to me. Another line is 19.Kf1 Bf3! (threat Qd1+; 19...Bc5? 20.Qxf6 defends f2) 20.Bxf3 Bc5! with threats against f2 and h8.

19... Bb4+??
Black wins after 19...Bg2!! The threat of Qc3+ compels 20.Rg3 or Rxg2, and Black then wins White's queen with 20...Bb4+
20. Rxb4??
It is especially embarrassing to admit that I was planning on 20.Kf1 Qd1+ 21.Bxd1 Rxd1+ and Re1#, not noticing that this is illegal because my rook is pinned on the back rank (by two major pieces!). But at least this is a mate. I'd been playing for it in some other lines where the Re1 is supported by a Nc2 instead of the bishop (after 17.Rb1, for example). There, it isn't even mate, as the king can go to d2!
20... Qc3+
Victor had overlooked that his Bc1 would be hanging here.
0-1

Here are a few of the games I had studied, with light notes.
(this is well-documented getting hit upside the head with a fish)

Kievelitz-Crouch, Decin 1996
1. Nf3 d5 2. d4 Nf6 3. c4 c6 4. Nc3 dxc4 5. e4 b5 6. e5 Nd5 7. a4 e6 8. axb5 Nxc3 9. bxc3 cxb5 10. Ng5 Bb7 11. Qh5 Qd7 12. Be2 Bxg2 13. Rg1 Bd5 14. Nxh7 Nc6 15. Nf6+ gxf6 16. Qxh8 O-O-O 17. Qxf6? (Rg8, of course, but White is still winning.) 17...b4 18. Bb2 a5 19. Bh5 a4 20. Rxa4?
(20. Qxf7 Qxf7 21.Bxf7 a3 22.Bc1 and Black's would-be pawn roller is already pre-undermined.)
20... Nxd4 21. Rxb4?!
(21. Ra2 Nc2+ 22.Kf1 (22.Ke2?? Bg2) 23.Bc6 and Black will have to play for an attack)
21... Bxb4 22. cxb4 Be4! 23. Qxf7 (23.Rg7 Nf5 0-1) Nc2+ 24. Kf1 Qd3+ (25...Qh3+ is also good) 0-1

Jiretorn-Chmielinska, European Women’s Ch, Warsaw 2001
This game shows what happens if White takes the exchange without playing 12.Be2 first.

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. e4 b5 6. e5 Nd5 7. a4 e6 8. axb5 Nxc3 9. bxc3 cxb5 10. Ng5 Bb7 11. Qh5 Qd7 12. Nxh7 Nc6 13. Nf6+ gxf6 14. Qxh8 O-O-O 15. Qxf6 Nxd4 16. f3 Nc2+ 17. Kf2 Bc5+ 18. Kg3 Rg8+ 19. Kh3 Nxa1 20. Be2 Nc2 21. Rd1 Bd5 22. g4 (and as you might imagine, Black won handily) Ne3 0-1

O'Cinneide-Hurley, Bunratty (Ireland) Open, 2000
And this game shows what happens if White tries to get fancy in the corner.

1. Nf3 d5 2. c4 c6 3. d4 Nf6 4. Nc3 dxc4 5. e4 b5 6. e5 Nd5 7. a4 e6 8. axb5 Nxc3 9. bxc3 cxb5 10. Ng5 Bb7 11. Qh5 Qd7 12. Nxh7 Nc6 13. Nxf8 Qxd4 (!!) 14. cxd4 Rxh5 15. Be3 a5 16. Be2 Rh4 17. Nxe6 fxe6 18. O-O-O Nb4 19. Bg5 Rh8 20. Bd2 Nd5 21. Kb2 Rf8 22. f3 Nf4 23. Bf1 Bd5 24. Rc1 Kd7 25. Rc2 Kc6 26. Rg1 Kb6 27. g3 Ng6 28. f4 Rac8 29. Be2 b4 30. Rgc1 Kb5 31. h4 Rc6 32. h5 Ne7 33. g4 Rfc8 34. Be1 Kb6 35. Bh4 c3+ 36. Kb1 R8c7 37. Bxe7 Rxe7 38. Bd3 Rec7 39. f5 b3 40. Rf2 a4 41. f6 gxf6 42. exf6 a3 43. h6 a2+ 44. Ka1 0-1

Moral of the story: all the sidelines in the 11...Qd7 line are good for Black; it’s only the main line that’s are completely lost!

Mate cluster #2

Mate 1) 20. Rxf7+ with Bh5+ and Qxf6#
Mate 2) 20. Qxf6+ with Qh8+ & Bg5+, with similar play; and
Mate 3) 20.Ba3+ which I consider emotionally equivalent to mate, even if it doesn't lead to a quick mate on the board

Here’s that longer mate at move 18:
18.Rg8 Qxa1 19.Rxf8+ Ke7

20.Rxf7+ 21.Bh5+ Now it's a mate in 8: 21...Ke7 22.Qxf6+ Kd7 23.Qf7+ Kd8 24.Qf8+ Kd7 25.Qd6+ Kc8 26.Qxe6+ Kc7/d8 27.Qd6+ Kc8 28.Bg4#

I have to say that after going over this game with a computer, I felt like it was a totally wretched game. However, after trying to find this particular mate myself, I have to admit it’s tough (or at least stressful) to do with (from the diagram position) mate hanging on c1 and the rook hanging on f8.
Likewise, a move before, it’s easy for the computer to see that 16...Nxd4 should be answered with 17.Qxf8, but it’s hard to notice that you should steel yourself and “ignore” the “loud” move Nxd4 and just play a sacrifice of your own. Another mental block in that position is it can be difficult to realize that you’re just winning so early in the game. On the other hand, Victor’s comments afterwards showed that he did realize he was winning, so

I suppose I can’t fault either of us much for missing the computer tactics on move 19; however, it was sheer luck that his ?? oversight outranked mine on move 20. Certainly not the most embarrassing game I’ve ever played, but it makes me think that perhaps one of the reasons chess is superior to roadrunner cartoons is that in chess both sides can get multiple anvils dropped on their head in the very same game.

Comments? I've added a poll.

Elizabeth and Lars have corrupted me

2009-09-07T17:24:00.000-07:00

Okay, I tried to keep this all chess, all the time, but (a) Elizabeth has been blogging about all sorts of random things for a while now and why should she have all the fun? and (b) my soon-to-be former workmate Lars has shown me one of the few golden opportunities I've ever seen to use the power of the internet to further the cause of world civilization.

So here it is: which of the following re-dubbings of the same rant from the movie Downfall are the funniest?

Hitler Learns that the Vikings Have Signed Brett Favre
Sample line: "Everyone who wears a Helga hat to bed, please leave. You must not hear what I have to say." (3/4 of the Nazis leave the room)

Hitler Learns That Michael Jackson Has Died and so Will Not Be Performing at his Birthday Party
Sample line: "And the worst part is, I never even got a chance to go to Neverland."

Hitler Finds Out He Has Been Banned from XBox Live
Sample line: "I had over 2000 Microsoft points!! I bought a Call of Duty theme pack, too!"

Note that I stayed away from less skillful ones, like "Hitler Learns there is no Santa Claus" or political ones like "Hitler Learns that Sarah Palin Resigned", but you can find them easily through the YouTube related links. And for the connoisseur, I understand that there is also a version of this up where Hitler is ranting about all the different versions of this that are up...

Two – no, three – Utterly Ridiculous Games

2009-07-22T05:57:00.000-07:00

Well, I was so bored the other day that I succumbed to the madness of reading Geurt Gijssen’s arbiter column on ChessCafe, and – as unfortunately so often happens with bad behavior – I was richly rewarded with the most ridiculous game I’ve ever seen, which someone had submitted for an official opinion.

I won’t have time to make anything like a real chess post for a week at least, so I thought I’d throw this out there – especially for any of you whose brain may have been fried by the 8 x 8 queens post.

The question was whether, in a game where White starts with his king and queen in each other’s positions, is the checkmate after
1.e4 e5
2.Bc4 d6
3.Kh5 g6#

legal? Or – more to the point – does the result stand in a tournament game?

The questioner quoted a whole bunch of rules relating to making an illegal move, which I didn’t read because I don’t really give a damn. Gijssen said that the more relevant rules were those governing pieces being set up wrong in the starting position – if it’s discovered during the game, the game must be restarted from the beginning (with, one hopes, the pieces set up correctly).

However, he added, since giving checkmate and pressing one’s clock ends the game, then the result of the game must stand, even though it would really pain him to allow it. He proposed several technical rule changes to allow such a game to be disqualified, which (of course) I didn’t read either, since if I’d been that bored I would have been banging my forehead against the computer, not reading stuff on it.

My main point in sharing is that this is just a hilariously ridiculous game, and it’s even more hilariously ridiculous to see an international arbiter approaching it seriously. I mean, this is a game where White (a) attempts the Scholar’s Mate while (b) not noticing that he’s moving his king to h5. What are the chances that this is going to occur in an event governed by the laws of FIDE?

Furthermore, I think that Gijssen is just dead wrong for two reasons:
First of all, what the hell are the standards for “discovering” that the pieces were set up wrong – or that an illegal move was made earlier in the game? It’s hard to imagine that Black delivered checkmate without “discovering” that it was his opponent’s king he was checkmating. I mean, unless he played 4...g6 and then went “Wait a minute! That’s your king!”

For Gijssen’s logic to be correct, both players have to have realized that the piece on h5 was a king immediately after (and only after) Black played 4...g6. After all, if White still thought it was a queen, he would have just retreated it to f3 and the game would have continued. To constitute “discovering” that the pieces were set up wrong, is Black somehow required to blurt out “Oh my God! That’s your king on h5! It must have come from d1, where it was set up incorrectly in the initial position and it was an illegal move to bring it out to h5!”? Give me a break. If Black delivered checkmate intentionally, it’s hard to imagine that he didn’t also realize that the king’s appearance on h5 was not quite kosher.

An alternative, of course, is that perhaps the helpful arbiter who submitted the question pointed out that a checkmate had occurred, when neither player had noticed it. (In this case, the arbiter should simply be shot, because he should have let the kids play) I have no idea what the rules are on continuing the game after checkmate, because (like I said) I’m not that bored. I’m just a bit intrigued by the ridiculousness of it all.

Okay: the second reason that Gijssen is dead wrong is that White should be forfeited on principle for attempting to mate on f7. Quite honestly, this should overrule all other considerations. Especially with children. Granted, perhaps this is a Nakamura game (blitz playoff?) where he decided to revert to his Qh5 repertoire, but in that case he should lose even more so, because it might influence young people.

I once had an eight year old student who would not accept that this strategy could possibly be bad. I lectured him sternly about the need to get all your pieces out, but he would not listen. “Okay,” I said, “we’re going to play a practice game.” This went:
Howard – Leon
CalArts, ~1990
1.e4 e6
2.Bc4 Nc6 You see, I have prepared for my opponent’s repertoire.
3.Qf3 Nd4
and here he joyfully picked up his queen to deliver checkmate at f7, only to discover that his bishop was blocked. And that he had a problem on c2. Consternation ensued.

(Here, actually, you see why this mindless checkmate goal is such a destructive meme: here’s a kid who – when he looks freshly at a position – can notice that not only his queen is attacked but there’s also a costly fork on c2. And yet, when planning his mate, he was so deeply on automatic that he didn’t notice that my e6 pawn blocks his bishop from f7)

The game continued:
4.Qc3 Bc5 I considered 4...c5, but thought it wouldn’t teach him as much about the importance of development if I won while behind in development. Luckily, the game finished very “instructively”:
5.d3?? Bb4
6.Qxb4 Nxc2+
0-1 because of 7...Nxb4 coming

A much nicer game, which actually accomplished its instructional purpose and got me the best parental response that I’ve ever had or heard of. Howard was a bit sulky after the game, so I thought it best to give his mom a little heads-up on what had happened.
So I drew her aside when she came to pick him up and said (quietly, out of the side of my mouth, like a secret agent) “We played a training game today, and I, uh, sort of kicked his ass.”
Mom: Well, I should hope so! We are paying you after all!

She also reported the following week that in his games with his father, Howard had taken to admonishing him over and over to get all his pieces out. It is good to have one’s instructions taken to heart.

If my math is right, Howard is almost 30 years old now. I wonder if he still plays chess.

The Third Ridiculous Game

When I started this post, I called the first game the most ridiculous one I’ve ever seen, but then I realized that wasn’t true. The most ridiculous chess game I know of goes
1.e4 e5
2.Qh5 Ke7
3.Qxe5#

But that’s just so offensively ridiculous that I won’t even give it a diagram. It does seem to show, though, that there’s a theme of an early Qh5 being associated with ridiculousness. Elizabeth Viccary just made a post where she mentions an argument among some players about what move is most often a good one (or bad one) – wherever it occurs in whatever game. I’d make a case for Qh5 to most often turn out to be a silly move.

8 x 8 Queens

2009-07-05T02:27:00.000-07:00

The famous Eight Queens problem has always fascinated me, perhaps because I’m so bad at it. The problem is to place eight queens on the chessboard in such a way that none of them attack one another (diagram shamelessly copied from Wikipedia).

I actually think that the reason it’s so fascinating to me is because I can’t see any pattern for the placement of the queens. I mean, a lot of the queens are a knight’s move apart, which only makes sense, since it’s the closest way to pack them without them attacking one another. But obviously this also gets broken quite a bit, and there turns out to be no simple heuristic as to where to start over once you’ve run your string of knight-related queens to the edge of the board (as happens on the left-hand side of the diagram).

This would also be why I’m so bad at it – because I can’t see any overall pattern. So ideally, to “subdue” this problem, I’d want to find a way to see patterns in it – by which I mean human-recognizable ones, not paper algorithms that can generate a solution but can’t be perceived over the board.

Another thing I’ve wondered about off and on is how many eight-queen solutions can be placed on a single board, where one is not allowed to put more than one queen on a square. In other words, can I put one set of eight yellow queens on the board such that none of them attack one another, then put a set of blue queens on vacant squares such that none of them attack one another, and so on for eight sets of eight queens?

Packing: the Rotational Approach
Now, these patterns are much too random-looking for me to just try mixing and matching them. One needs a heuristic. The first one involved packing a whole 8-queen pattern into one quarter of the board via rotation.

For instance, if I give the board three quarter-turns, and on each turn I “trap” whatever queen is in the lower-right, then I’ve packed all eight queens into one quarter of the board. If I can do this without any of them landing on top of one another, I’ll have proved that the initial position can be rotated four times to give us four solutions that fit on the same board. The diagram below shows how our initial position fails this test:

Here I’ve colored the home square of each queen, and colored the square that it packs to (in the lower right) the same color. Six of the queens rotate without interference, but the two on the magenta squares map onto one another, ruining the situation.

Well, let’s not try to break down an existing pattern – let’s try to generate one of our own. And let’s not bother with the four rotations, let’s immediately test for eight.

Generating our own solutions
This quarter of the board can be split in half down the long diagonal. If I can take each eighth of the board and spin it out into a valid eight-queens pattern, then the way I’ve generated it will prove that (a) it can be spun three times to give us four non-interfering eight-queens patterns, and (b) it can then be flipped across the long diagonal to give us four more – our ideal solution of eight non-interfering patterns.

It’s not quite as simple as that, because the long diagonal squares can’t each be divided in half. But one can split them two and two: for instance in the diagram above, one can take the set of the six yellow squares plus the two deep blue ones on the long diagonal, and then take the set of the six light blue squares plus the two black ones on the long diagonal. If both sets can be spun out into a valid eight-queens pattern, it will show that it is possible to fit eight sets of eight queens on a chess board.

It is fairly easy to show that this is impossible. Let’s start with the central dark blue square and work our way down the column of yellow squares beneath it:

Already, ominously, there is only one rotational slot possible for the second square (possible rotations shown in green). And there is only one for the third square (shown in magenta). By the time we get to the fourth square, there is no space available for it that doesn’t attack an already placed queen.

The reason for this is easy to see: we’re starting out with four squares on the same column, and there are only four rotations available. Therefore, we have to distribute our rotations with optimum efficiency, one queen each on the two central columns and two each on the two central rows. But queen number one is already on both a central column and a central row, taking up two slots. Thus, we can only add two more queens before running out of slots. The exact same problem applies with the corner square.

I believe that there are similar issues with light-blue-centered eighth of the board, but those would be more complicated to demonstrate. In the meantime, it’s clear – there can be no fully 8x8 queen solution generated in this way.

Is this a packing problem or a tiling problem?
Well, this got me thinking about approaching the problem in a related way: these rotational rings of queens don’t attack one another; so if I can find a pair of rings that cover the whole board without attacking one another (a) it’ll be pretty cool and (b) it might open the way to seeing other patterns.

Well, that doesn’t work. In fact, if we make a ring of queens that are on rotations of the square e3:

We find that just two more queens (in the lower left and right corners) completely cover the board. Now we’re starting to get more human-grokkable patterns, but we’re also straying a bit from the task. So I started to wonder: is this a packing problem or a tiling problem?

It’s sort of a mixture of each: if it’s a packing problem, then it’s to find the most efficient packing given a constraint (queens can’t attack each other) that makes the packing very inefficient; or, if it’s a tiling problem then it’s to find the least efficient tiling given a constraint that tends to make the tilings maximally efficient. This is an issue especially with our 8 x 8 queens task, since it's actually a packing of a packing (or a packing of a tiling?).

Okay, so let’s take a look at whether this ring of queens idea can give us patterns that need less than six queens to control (or occupy) the whole board. One does not have far to look for a generalized solution!

For each non-mutually-attacking rotational ring of queens outside the central sixteen squares, the four queens in the ring leave exactly four squares uncovered. These squares are symmetrically distributed on the long diagonals, so that one more queen on any of these four squares covers them all and completely controls the board.

In other words, now that we’ve shown that e3 needs six queens to cover the whole board, the five remaining yellow squares from our original eighth-board formation all have five-queen solutions to the problem of covering the whole board. Here are those formations:

e2 (I’ve just colored the appropriate squares rather than drawing actual queens)

f2

e1

f1

g1

A few points here:

1) I think this exhausts the solutions possible with five queens. I don’t have a proof, but these five patterns strongly exploit both the rotational symmetry of the board and that of the queen herself. As soon as I mess up the symmetry, the solutions start requiring more queens.

2) I will hold out the possibility that there may be a solution with four queens, randomly and brilliantly placed (sort of like the famous problem of how to connect nine dots with only four straight lines). But I think the probability of this is low.

3) Among these five solutions, each uses a different long diagonal square except that two use the corner. However, you can see that I have cunningly notated one corner in the lower left and one in the upper left (all other long diagonal squares are in their lower left rotation). This means that (a) we can place each of these five solutions on the chessboard at the same time without any queens landing on top of one another, and (b) we can then flip this composite solution horizontally to give us a total of ten solutions packed onto the same chessboard.

I like this.

Update: after writing all this, I did some online research and found out that there already exists a proof that five queens is the minimum number to completely cover an 8x8 chessboard, and that moreover there are 638 “basic” solutions that can be rotated and reflected to produce a total of 4860 distinct positions satisfying the condition. But intriguingly, the position given as an example follows the same form as my five solutions: a ring of four queens plus one “cleaning up” on the long diagonal. I wonder how many of the solutions follow this form.

Back to the original problem
Can this shed any light on our original problem of the eight queens, and how many of them can be packed onto a chessboard? It does. Let’s take a look at Wikipedia’s solution #1 again:

Although the presence of queens at d8 and h5 mean that this solution can’t be rotated a quarter-turn in either direction, it can be rotated 180 degrees. That gives us the following pair of solutions, notated here with red squares for the original queens, and blue squares for the rotation:

Now I call that an amazingly regular pattern – one that is very human-understandable! First of all, this is a pair of solutions packed onto the same board. But one can also easily see by looking at the pattern that it can be flipped either horizontally or vertically without any of the queens landing on top of one another. But then it can’t be flipped again, because either of these flips gives us the same composite pattern of four solutions packed onto the same board. (This is actually a result of the operations we’ve done, since flipping horizontally followed by flipping vertically is the same as rotating 180 degrees)

Looking at the existing “basic” eight queens solutions (there are only twelve), there aren’t any whose composite patterns of four magically compliment one another, giving us the ideal eight solutions. However, there is at least one pair of eight-queen patterns where the solution and one reflection can fit into the space left by the full composite of another.

Each of the twelve basic solutions must also be a distinct eight-queen pattern in either of its reflections, since for a reflection to have a queen land on top of another means that those queens must have started out on the same row or column – an impossibility giving the starting restrictions. Each of the twelve basic solutions also possesses exactly one non-interfering rotational version. All twelve patterns contain at least one pair of queens that interfere with one another rotationally, but those that contain two pairs interfere with each other at the same number of rotations.

So each basic eight-queen pattern can be packed onto the board with exactly three other versions of itself. And once this is accomplished, there is at least one pair of basic patterns where two permutations of the second pattern can be packed onto the board with the full four permutations of the first.

Let’s take a look. Here is Wikipedia’s pattern #2:

In passing: I like the way this pattern contains two permutations of my e3 tiling covering the chessboard with six queens:

Okay, here is Wikipedia’s #2 pattern rotated 180 degrees and then flipped horizontally (or vertically):

So far, so good.
All right, here is Wikipedia’s pattern #12:

You can see that it fits in the blank spaces left in the diagram just above it. Let’s flip this one horizontally:

This one fits, too, so let’s put them all together:

This gives us six eight-queen patterns packed onto a single chessboard.

Okay, summing up:

1) I think that this is a maximum packing for eight queens. Just looking at the twelve basic solutions, they all interfere with themselves or one another if you try to do more than six on a board. This is still a very concrete result, though, achieved by spot-checking the twelve basic solutions for rotational interference. I have no idea how to give the result (generalized or specific) in theoretical terms – for starters because I have no idea if there exists any way to represent the basic solutions themselves in theoretical terms.

2) I find it interesting that the five-queen solution can be packed onto a chessboard ten times, and the eight-queen solution six times – as close to being inverses of one another as the number of queens being used allows. One occupies 50 total squares on the chessboard and the other 48. I wonder how this number will behave for other numbers of queens on other sizes of chessboard. I imagine that as the board gets larger, it will become possible to fill a larger and larger proportion of the available squares with queens – by an analogy with knot theory, where as you increase the number of dimensions, it becomes easier and easier to slip out of a knot, and also because as the board increases in size the queen becomes proportionally less powerful.

My First Sicilian

2009-06-28T01:55:00.000-07:00

There are first things we all remember. This is my first Sicilian. After years of being a Réti player, I was getting good positions out of the opening, but it was taking me too long to win them. I was tired of winning a game in the morning that took six hours and then having to play the second game of the day after a 20 minute break and (often) no food.

I tried switching to the English, but that wasn’t enough, so eventually I went whole hog and decided to switch to 1.e4 (a decision from which my rating has still not recovered). Anyway, my main fears about this shift were assuaged when I bought Nunn & Gallagher’s Beating the Sicilian 3. I have never been able to understand why Black doesn’t just always get mated in the Sicilian, but the statistics are very clear that there must be some reason. So I figured I’d by buy the book, use it in an email tournament (with the IECG) and by the time that was done I’d have enough quality experience to play it over the board.

Shernoff-Dunn, IECG Cup 1997
1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.f4

N & G’s recommendation against the Najdorf.

I was happy with it because I figured it wouldn’t have as much theory as the Bg5 lines, and because I’d seen a game with it where Korchnoi beat Geller in a style similar to that which I was hoping to achieve by switching to 1.e4.

6...Nc6

Okay, now we’ve got all the knights developed on normal squares, just like I was taught as a wee lad when I was first learning about chess. Let’s be good and look in the book...

What? This is not a normal move? In fact, it’s so much of a sideline that it gets kissed off with “7.Nxc6 bxc6 8.e5 Nd7 9.Bc4 dxe5 10.0-0 e6 11.f5 Bc5+ 12.Kh1 and White has good attacking chances.”

What? I paid $23.95 for one little line, and to be told that I have good attacking chances?

7.Nxc6 bxc6 8.e5 Nd7 9.Bc4 dxe5 10.0-0 e6 11.f5 Bc5+ 12.Kh1

Son of a gun, he played into it. And now, as so often happens, that little untested line turns out to have a completely incorrect evaluation. On my very first use of that expensive book. Thanks, N & G!
12...exf5? 13.Rxf5 f6
My opponent, in New Zealand, always played very quickly (on a couple of occasions we exchanged three move pairs in one day) and was always happy to play “anti-positional” moves like this in order to hang on to material. Characterizing his play as quick, materialistic, and anti-positional, I decided he must be using a computer. (This is how they played, back in the day.)

In retrospect, I’m not sure why I thought that, since Black (from the diagram) has the much better and more materialistic move 12...Nb6!, after which White will either have to exchange queens or sac unsoundly in order to remain only one pawn down – for example 13.Bd3?! exf5 14.Bxf5?? Qxd1. I also don’t think much of 13.Qf3 Nxc4 14.Qxc6+ Bd7 15.Qxc5 Rc8 and exf5. This is not why White opens with the e-pawn.

Okay, so I’ve dodged a bullet here, but I still have to address the threat of Nb6, and I have to find a constructive place to develop my queen’s bishop, otherwise my lead in development will just melt away.

You might want to take a moment or two to contemplate how you would solve these problems...

14.Nd5!

My first Sicilian, and I get to sac a knight at d5. Sweet!
15...Rf8?!
This was what I had expected, but 15...Rb8 is a much more constructive way to threaten to take the knight.

On 14...Nb6, White does not play the humorous line 15.Nxb6? Qxd1+, but instead 15.Nxf6+ Ke7 (15...gxf6 17.Qh5+ with widespread devastation) 16.Bg5! with that nice bishop development that I’d been aiming at – for instance, White has a nice checkmate after 16...Qxd1+ 17.Rxd1

You might want to stop here and try to spot the various mates.

The easiest is 17...gxf6 18.Bxf6+ Ke8 19.Rd8#

Then there's 17...Bxf5 (covering d8) 18.Nh5+ Ke8 19.Nxg7#

And the prettiest one is 17...Nxc4 18.Ne8+! Ke6 19.Nxg7#. It would have been difficult to spot this over the board...

Back to the game
(after 14...Rf8)

15.Qh5+ g6
16.Qxh7 cxd5
17.Qxg6+ Ke7
18.Bxd5 Rb8
19.Bh6

And there’s that nice bishop development that was the whole point of the combination. I was glad I was playing this game via correspondence. It would have been tough and stressful to find all of this over the board.

At the time, coming off all those Rétis of mine, this seemed like a completely crazy position to me, but now as an experienced 1.e4 player, it seems completely normal! Well, not. But I certainly feel quite confident in saying that White has good compensation for the piece.
19...Rxb2

Again, I felt that this was an inappropriately materialistic move. On the other hand, 19...Nb6 20.Qg7+ Kd6 21.Qxf8+ (21.Be4 Bxf5 22.Bxf5 Rg8 23.Rd1+ Bd4 and I don’t think I have quite enough) 21...Qxf8 22.Bxf8+ Kxd5 23.Rxf6 and I should be able to win this endgame.

20.Bxf8+ Qxf8
21.Bb3 Bd4
22.Rd1 Nc5

23.Rh5
The rook will be very active on the 7th rank. Meanwhile, my Qg6 is active enough; and it defends c2, keeping the Rb2 confined.
23...Nxb3
24.axb3 Be6
25.Rh7+ Kd6

See my comment above about this position now looking normal. In Rétis, the whole point is not to give your opponent any counterplay whatsoever. Umm, not that Black really has any here. But one never has to calculate as many tactical lines in the Réti as I’ve had to do here, unless you’ve screwed up badly and let Black off the hook. So although I kept telling myself that things were fine, my positional alarm bells kept giving off danger signals. And there were certainly a lot of tactics here that I might have missed over the board.
26.Ra7

on 26.c3 Bd5, the weakness of g2 may cause me some problems. Better to not touch anything major, and just push my h-pawn.

26...Ra2 An unusual way to defend the a-pawn.

27.h4 Kc6
28.Rh7
I have no idea why I did this.

28...Qg8
I have no idea why he did this.

29.Rg7 Qd8
30.h5 a5
31.h6 Kb5
What is Black doing with his king?

32.c3??
I have no idea what came over me. It is foolhardy to open the second rank, and I soon get into trouble because of it. I should just push the h-pawn, of course. I think I was motivated by the fear that his queen might move off the d-file and I’d lose the pin, and also that 32...Bd5 can currently be met by 33.c4+

32...f5 In an over-the-board game, I might have missed the threat of Qd8-h4. This is why he ran with his king – so that Qxe6 isn’t check.

33.Qh5 Bxb3
34.Rb7+?
Because I was so upset over the course of the game, I decided afterwards that this was a mistake, and I should have played 34.Rb1. This seems correct, although the position has still gotten even more nerve-wracking than it needs to be.
34...Kc6
35.Rxb3

This was all part of my plan when I played 32.c3, and I was expecting Black to resign now. After all, I’ll be a full rook up in a moment.
35...Qg8
Huh! Sort of like a spite check! A spite mate threat. I just defend, and then... he... takes my rook on b3. Son of a bitch! Emotional pandemonium!

Luckily, in correspondence chess one can go downstairs and watch back-to-back episodes of Wings and Bewitched to calm ones nerves.

You might want to take a bit of time now and figure out how White gets out of this situation.

36.Qf3+ e4

37.Rb8! exf3
After 37...Qxb8 38.Qxf5, saving the bishop loses the rook to Qe6+, and 38...Qg8/g3 is met by Qxe4+ and cxd4, when Black is in a world of hurt, since White’s queen covers the perpetual (after 38...Qg3) by Qf2-h4 and back. This last is also quite hard to notice over the board, since my main focus for Qxe4 is guarding g2.
37...Qg5 may be the best swindling try (38.Qf1?? Qh4#) but 38.Qh3 holds things down surprisingly well.

38.Rxg8 And the rook covers g2

38...Be5
And here I thought that 38...f2 39.cxd4 Re2 was a better chance, though in correspondence it’s not difficult to find 40.g4 with Kg2 to follow.

39.Re8 fxg2+
40.Kg1 Bg3
41.h7 a4 Around here, I decided that a computer would not have shed material so fast, and gave up the idea that he was using one.

42.Ra1 42.Rd3 may be more accurate, chasing the bishop instead of the rook. His rook can (and should) just move back and forth on the 7th rank.

42...Rxa1+
43.Kxg2 Bd6
44.h8Q Ra2+
45.Kf3 1-0

After the game, I mentioned the quick play and the computer idea, and he said “Oh, no! It’s just that I play at work, so I always have to move very fast, before someone sees me.”

Pretty Drawing Line Busted

2009-06-11T11:02:00.000-07:00

I've added something at the end here, since Blogspot isn't allowing me to post comments to my blog. This seems to be a known problem that they haven't fixed -- there are a few threads in their help forums complaining about it.

Alas, I busted my favorite line in this whole endgame on my way home from work yesterday. You will recall one critical position, which in my home notes is labeled “The Last Crossroads” (and I have now added that title in the original post).

The Last Crossroads

Here I gave three different tries for Black:

61...Nd3, toying with queening the queenside pawns
61...Nd4+ 62.Kb1 Ndb3, forcing the queening of a queenside pawn, and
61...Nd4+ 62.Kb1 Nce2, threatening mate and forcing a draw. This last line is the one that I thought the most correct, and also the most attractive. However, it seems that White has a superior option: after (61...Nd4+ 62.Kb1 Nce2) 63.Ka2 Nc3+ 64.Kxa3 b1/Q

The line that I gave in my original post is 65.Rxb1 Nxb1+ 66.Kb2 Ne6 =. However, this particular position always bothered me, in that sort of nagging way that all too often turns out to be significant. White sort of has a little breather here, because his king isn’t being checked. However, what can he do other than take the queen, right? – because he’s threatened with mate on the move. Wrong! He can under-promote:
65.f8/N+! Kh8
66.Rxb1 Nxb1+
67.Kb2 Nd2
68.Kc3 N2f3

and for the moment Black has preserved his extra knight, but he’s not happy about it. For one thing, White can win the knight back at will by pushing his e-pawn. At the moment, that would also lose the h-pawn, so probably White should start by protecting that by pushing his g-pawn (perhaps preceded by Kd3-e3/e4. None of Black’s pieces can really move (especially once White plays Kd3-e3, tying down both knights). Black may be able to draw if he gets two pawns for one of his knights, but in all these lines it's White who's playing to win.

It’s no good trying to avoid this with

65.f8/N+! Kg8
66.h7+ Kf7
67.Rxb1 Nxb1+
68.Kb2
and now Black has to come back with Kg7 to keep the h-pawn from queening, so White gets to take the Nb1. 66...Qxh7 67.Nxh7 is also awful. So it looks like Black would have to go for complicated swindling chances in one of the other tries.

A complex ending with knights

2009-06-08T02:38:00.001-07:00

I was spurred to make this post (my first ever) by the surprising amount of debate over a knight endgame post by Elizabeth Vicary: http://lizzyknowsall.blogspot.com/2009/05/i-fail-to-win-knight-ending.html
What surprised me most was how poorly the commenters seemed to understand each other’s standards for whether an ending was simple or complex. Gee whiz, here I am, all freshly signed up on blogspot so that I can engage in dialog, and I might not be understood! I’m not posting stuff just so that I can be misunderstood!

So I thought maybe I’d post an interesting endgame that veers (especially in the sidelines) between complex, simple, and extremely complex. That way, whenever anyone misunderstands when I call an ending simple or complicated, I can just refer them to this post and my personal standards (whether or not you agree with them) will become perfectly clear.

Bacon – Shernoff, World Open, 2002 (Round 1)

We reached this ending after an exciting but poorly-played middlegame: first I allowed White to sac a bishop for all three pawns in front of my king, obtaining a dead won position. Then, in time trouble, White declined to push the center pawns that you see in the diagram, or to keep kicking my king around; instead he won an exchange and exchanged queens. I assume he was afraid of hanging material, or just thought the ending must be dead won with his material advantage.

White had made the time control with two seconds to spare (the magical precision of digital clocks!) and then gone outside for a smoke to calm down. So at this point he had about 50 minutes left in the sudden death time control, and I had about half an hour more.

I’ll return to the question of what White should play here at the end of the post. In fact, this is one of a few issues that I’ve broken off into its own post below this one, so that we don’t get our threads tangled. Or at least keep them minimally tangled. I want us all to be understood, after all...
45.Kf2 Nb4!
46.Re4 Nd3+
I felt that the b-pawn was the better one to steal, since my knight is nearer the center and it’s easier for it to jump back into action (for example, Nc3 is impossible if I take on a2). There are also some neat coordination things that happen between the Nb2 and the pawn I’m trying to queen. For one thing, the idea of Nd1, momentarily blocking the back rank, becomes thematic.
47.Ke3 Nxb2

White’s original intention here may have been to simplify, but that loses:
48.Rxd4 cxd4+ 49.Kxd4 b4 50.h4 b3 51.axb3 a3 52.Kc3 Nd1+ 53.Kc2 a2 queens.

When I showed this game to my friend Todd Rowland, he suggested 48.Rh4, which just goes to show that when you randomly lose material in an ending it’s not necessarily bad. Black has to take the rook, since if White gets to play Rh8-b8/a8, Black will never make any progress on the queenside:
48.Rh4!? Nf5+ 49.Ke4 Nxh4 50.gxh4

and this has become an extremely complicated ending, since Black can’t queen his pawns and also get his knight back quickly enough to stop White’s pawns: after 50...b4 51.Kf5 Nc4 52.e6+ Kf8 53.Kg6 Ne5+, Black is involved in tricky maneuvers of trying to impede White from queening while pushing his own pawns.

After 50...b4,

White also has the alternative of 51.h5, forcing a new queen. Then best play seems to be something like 51...b3 52.axb3 a3 53.h6 a2 (53...Kg6 54.e6 Kxf6 55.h7 is not an improvement, as White queens first) 54.h7 a1Q 55.h8Q Qh1+ 56.Kf5 Qf3+ 57.Kg5 Qg2+ 58.Kf5 Qg6+ 59.Kf4 Nd3+ 60.Ke3 Nxe5=

This was my analysis shortly after the game. However, looking at it with fresh eyes just now, I decided that there’s actually no need for Black to spend tempi queening his pawns now, since White can’t stop them later on. This means that if you see the right line (or have the right idea) it’s actually a simple endgame after all:

50...Ke6 (stopping Kd5, attacking the queenside pawns) 51.h5 Nc4 52.h6 Nxe5 53.h7 Ng6 and Black wins.
Unfortunately, this line allows White at least a draw with (51.h5 Nc4) 52.f7! Kxf7 53.Kd5. So it’s still a simple ending – just with the wrong evaluation. In fact, White can even play for the win with a-pawn and h-pawn(s) vs knight. So it looks like Black has to embrace the complications in this line to have any winning chances at all. And it certainly looks like White’s best winning try in this ending.

Back to the game:

48. Rg4 Ne6 49.h4 b4 50.h5 b3 51.axb3 a3
51...axb3? 52.h6 c4 53.h7 Nd1+ 54.Kd2 c3+ 55.Kxd1 Nc5 56.h8Q c2+ 57.Ke2

52.Rh4 c4! 53.Rh1
53.bxc4?? Nd1+ and the a-pawn will queen. If White was a GM and won this game, no doubt s/he would draw our attention to the maneuver Re1-e4-g4-h4-h1.

53...cxb3 54.h6 Kg8 55.Ke4
If 55.f7+ Kh7

55...Na4
Again, looking at this position with fresh eyes, at first I thought this was a mistake that gives Black a chance to draw. The new line I saw is 55...a2 56.Kd5 (if 56.Ke3 Nd1+ and ...b2) Nf8/g5 with Nd1 on the next move and Black will queen. But this only works if White doesn’t play 57.e6 (and f7+ followed by h7). Back to the game:

56.Kf5?
White has to play Kd5. As in the famous Reti study shown here, the king has to move diagonally between his two goals, feinting at the kingside in order to reach the queenside in time.

After 56.Kd5 Nac5 57.Kc4 I was anticipating situations where my Nc5 and two pawns get exchanged for his rook, with his king recapturing way down in the corner. This gives my K+N plenty of time to round up White's remaining pawns, drawing. I’ll call this the queenside liquidation strategy.

57...b2 58.Kc3 Nd3 59.f7+ Kh7 60.Kb3 Nc1+ 61.Kc2

The Last Crossroads

and again, similar to the exchange sac above, there are three lines that Black can choose, one of which makes things very clear and two that entail more complexity.

Try 1
The clear one is 61...Nd4+ 62.Kb1 Nce2 (I like this line not only because it’s clear, but also because I get to threaten a nicely geometric perfect mate with Nc3+) 63.Ka2 Nc3+ (63...Nc1+ 64.Kb1 also repeats) 64.Kxa3 b1/Q 65.Rxb1 Nxb1+ 66.Kb2 Ne6 and here we have the simplest implementation of the queenside liquidation strategy.

Try 2

The more complicated line is 61...Nd3 62.Kb1 (to stop the a-pawn; 62.Kb3 Nc1+ repeats) and Black now has a couple ways to try and implement Nd2/c3+ and b1/Q, ending up with the queenside liquidation as above. I’m pretty sure that I was planning 61...Nd3 during the game, since it is the starting point of my analysis immediately afterwards.

Unfortunately, for instance after 62...Nxe5 63.Re1 Nf3 64.Re2 (not 64.Rxe6 Nd2+) White will get to play either Rf2 with the idea of f8/Q, or Re3xa3. Or after 62...Nf2 63.Re1 (covering e4 and d1) and Black seems to be in zugzwang. He can’t really move either knight, and if he moves the king White can force him to take the h-pawn by pushing it. Then he can play Ka2 and capture the a-pawn, as Nd3 (with the idea of Nc1+) can be met by Rh1+ and Kxa3.
If Black loses his pawns, the best he can do is a draw (even if White magically loses his rook) since White’s pawns are so far advanced; so he should prefer the simple drawing line of Try 1.

Try 3
The other factor that makes this continuation extremely complicated is that Black can force a new queen of his own, but only at the cost of allowing White to queen also. This is not a good bargain for Black. While we’ve all heard a million times what a strong attacking force Q + N are in the endgame (so Q + 2Ns should be even better, right?), for hunting down a lone king on the open board, they really kind of suck. Q + R is what you really want for that, and that’s what White has. Since White pretty much has Mate On Tap ™ as soon as he queens, Black has to mate with all checks, but it’s pretty easy for him to just walk away from the knights while staying on the same (correction) opposite colored squares as them, which makes it impossible for them to catch up with check. Here is a sample of the issues:

After 61...Nd4+ 62.Kb1 Ndb3

White can try for a perpetual check on f8 and g6 with 63.f8N+ Kh8 64.Ng6+ Kh7 65.Nf8+ but now black plays for the win with 65...Kg8 66.h7+ Kf7 67.h8/Q a2+ 68.Kxb2 a1Q+ 69.Kc2 Qa2+ 70.Kc3 Qd2+ 71.Kc4 Qd3+ 72.Kb4. Now the White king is confined, and Black wins by bringing up his remaining piece: 72... Na2+

73.Ka4 (73.Ka3 also Nd4+ mates simply) 73...Nc5+ 74.Ka5 Qa6 mate.

But all this means is that White should queen immediately with 63.f8/Q instead of screwing around with perpetual via the underpromotion. Now the mating line in the last diagram doesn’t work because the Qf8 guards c5, and I have been unable to find another way for Black to prevent the White king from just walking away. Try it. I know that most of you can just dump the position into your computer and it will be perfectly happy to spit out a string of 79 checks (if such exist) leading to mate. This is irrelevant to what you can find at the board with 30-40 minutes on your clock, after the fatigue of what I’d had to find already. I’ve put a post about the position after 63.f8/Q after this one. I’m interested to hear people’s thoughts about how this analytical task can be approached sanely and practically at the board.

Back to the game:

Now (after 56.Kf5) we have a simple ending for the first time in the actual game.

56...Nac5 57.g4 a2 58.g5 b2 59.g6 b1Q+ 0–1

The Ne6 forces the white king back, so after 60.Kg4 Qxg6+ 61.Kf3 Qe4+, Black wins the rook in the corner anyway.

If White had played 56.Kd5 he could have also tried this continuation, since queening as in the game is not check and loses to 60.h7+ Kh8 61.g7+. But instead Black could play 59...Nf4+ 60.Kxc5 Nxg6 and b1/Q on the next move.

“Do Not Hurry” vs Complexity

2009-06-08T02:37:00.000-07:00

This standard bit of endgame advice is fairly ludicrous in this game. All sorts of things are decided by a single tempo. But with this in mind, maybe we can use “Do Not Hurry” as a test for developing a scale of complexity for endgames:
1) In the simplest endings, “Do Not Hurry” does not apply, as you can simply count out what you should do (straight-ahead pawn races for example). In these endgames it’s quite clear who has the advantage, and what each side needs to do.
2) Add a bit more complexity, and “Do Not Hurry” starts to apply, but these are all positions where nothing much is going on, and the critical task is coordinating responses to fairly low-urgency threats.
3) At a higher level still, you have something like this game, where each tempo matters, and both players are working with threats that are quite urgent.

What should White have played in the initial position?

2009-06-08T02:34:00.000-07:00

Given the course of the game, I originally thought that White’s rook should have just stayed on the back rank, and White should have just played Kg2 and pushed the h-pawn in the initial position. I felt that White’s initial Kf2 let Black develop his ferocious activity, so it was mistaken; however, (a) the centralized king that White has in the game is not worthless either, and (b) Black has some activity anyway:

However, it turns out that Black can still respond with Nb4, and after Nd3 White will still have to play Re4 if he wants to keep the e-pawn (and he does want to keep the e-pawn, right?). Given the success of the exchange sac in the notes, I also thought that maybe just pushing the h-pawn here would be good, with
54.h4 Nf3+
55.Kf2 Nxe1
56.Kxe1 and then if Black tries to play as in the game,
56...Nb4
57.h5 Nd3+
58.Ke2 Nxb2
59.h6 and the pawns are ready to carry the day; but obviously Black doesn’t have to be so cluelessly persistent about winning the b-pawn. It is ironic that these accidental-looking exchange sacs can both be so dangerous.

How to handle Q + 2Ns vs Q + R?

2009-06-08T02:29:00.001-07:00

Okay, here’s this position. How do you evaluate it? Is there any way to parse the possibilities in a sanely human kind of way, to reach judgments in a reasonable amount of (over the board) time?

It’s ominous that Black has to give up either a pawn or a knight in order to queen. That pretty much means he has to mate or die.

In the main post, I examine a line where Black promotes his a-pawn at this point. There’s also 63...Nd2+ 64.Kc2 b1/Q+ 65.Kxd2 Qb2+ 66.Ke3 Qc3+, which looks promising when you see 67.Ke4 Qd3+ 68.Kf4 Ne2+ and Black will either win the queen with a queen check on the f-file or by playing 69.Kg4 Qxg3+ 70.Kh5 Nf4+. However the king can simply go 67.Kf4 (a move earlier), or to f2 here. Black may have a perpetual, but it will be difficult. And if White gets the queens off, he has a clear win: 67.Kf4 Qd4 68.Kg5 Qxe5+ 69.Qf5+ Qxf5 70.Kxf5 Nb3 71.Rh2 Nc1 72.Rc2 and after White wins the a-pawn he should be able to queen the g-pawn.