Friday, May 15, 2009

Sacrificing the Queen for Two Minor Pieces (Part 2)

Ehlvest goes berserk! Nakamura's queen sacrifice in the second round of the U.S. Championships must have made a strong impression on his opponent, Jaan Ehlvest. A mere, three rounds later Ehlvest himself sacrificed his queen for bishop and knight against Varuzhan Akobian. Unfortunately for Ehlvest, his moment of inspiration did not work out very well.

1. e4 e6 2. d4 d5 3. Nd2 Nf6 4. Bd3 c5 5. e5 Nfd7 6. c3 Nc6 7. Ngf3 Qb6 8. O-O cxd4 9. cxd4 Nxd4 10. Nxd4 Qxd4 11. Nf3 Qb6 12. Qa4 Qb4 13. Qc2 Nc5 14. Bd2 Qa4 15. b3 Qd7 16. Nd4 Qd8 17. Rac1 Bd7 18. Be2 Ne4 19. Nb5 Bc5

Ehlvest has sacrificed a pawn in a French Tarrasch, but does not appear to have much compensation in this position. The only thing he really has going for him is that Black's king is still in the center. White's knight is ready to harass the king from d6, but Black's dark-squared bishop and knight are both covering that square. But how can White deflect them from the defense of d6? 20. Be3 seems like a plausible move. There are then a lot of potential variations to evaluate:

a. 20...a6? 21. Bxc5 Bxb5 22. Bxb5+ axb5 23. Bb4 gives White a nice advantage, with the Black king stuck in the center, strong dark-square control, and the Black knight in danger of being trapped.

b. 20...Rc8 21. Bxc5 Rxc5 22. Nd6+ Kf8 23. Qb2 Rxc1 24. Rxc1 Nxd6 25. exd6 Bc6 26. Qe5 and White has good compensation for the pawn, because Black's rook isn't in play.

c. 20...Bxe3 21. Nc7+ Ke7 22. fxe3 Rc8 23. Bd3 Bc6 24. Bxe4 Qxc7 (24...dxe4?? allows 25. Qc5+ Kd7 26. Qd6 mate!) 25. Bd3 Qxe5 26. Qc5+ Ke8 27. Qxa7 seems unclear. Black is up a pawn but his king is stuck in the center. White queen is off-side while Black's is nicely centralized. White also has to watch out for his king's position.

In any event, 20. Be3 seems playable, although there were a lot of complicated variations to evaluate. Ehlvest's way of breaking through to the d6 square is more elegant:

20. Qxc5?!?! Nxc5 21. Nd6+ Ke7 22. Rxc5

Monday, May 11, 2009

Sacrificing the Queen for Two Minor Pieces (Part 1)

The long-term positional sacrifice of the queen for two minor pieces is perhaps the most fascinating and difficult to evaluate type of material sacrifice. According to the counting scheme inculcated in all of us from very early in our chess education, two minor pieces (6 points) should be completely inadequate compensation for the queen (9 points). After all, even rook and a minor piece (8 points) is insufficient compensation for the queen.

Some creative players have attempted to show, however, that in the right kind of position, two minor pieces can hold their own against the queen.

One of the earliest, most famous, and most important games to feature this kind of sacrifice was played between Boris Spassky and David Bronstein at the Amsterdam Candidates' Tournament in 1956.

Boris Spassky-David Bronstein
Candidates Tournament (12), Amsterdam 1956

1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. f3 e5 6. d5 Nh5 7. Be3 Na6

At the time, the normal moves in this position were 7...f5 or 7...O-O. Tal had played the former move against Spassky a couple of months earlier at the 23rd USSR Championships; Spassky won in 38 moves. Ragozin had been the first to play 7...Na6, in a game against Tolush from the same Soviet Championship tournament. Ragozin had reached a passive position, however, after 8. Qd2 Bd7 9. Bd3 c5 10. Nge2 Qh4+ 11. g3 Qe7 12. a3 Nc7 13. O-O-O a6 14. g4 Nf6 15. h4.

Bronstein had a different idea. What if, rather than waiting for White to play Nge2 and cover g3, he played the queen check a couple of moves earlier? Of course, if Black plays ...Nxg3, White can also pin it with Qf2...

8. Qd2 Qh4+ 9. g3

9...Nxg3!!?? 10. Qf2 Nxf1 11. Qxh4 Nxe3 12. Kf2 Nxc4

Monday, May 4, 2009

My Favorite Moves (1)

I am going to start another series of occasional posts, in which I highlight some of my favorite moves. This is not meant to be a compilation of the "greatest" moves ever made, but is rather a selection of my personal favorites, based on my own subjective, aesthetic criteria. To the extent there is a pattern or theme to the moves, I think they are all moves that have a certain paradoxical quality. Many of them are superficially bizarre or rule-breaking, but on a deeper examination, are in fact completely logical. They are almost all moves that it would never have occurred to me to play.

The first move is justly famous will probably be familiar to most readers. I still remember the thrill I felt when I first saw this game, however, and it still gives me pleasure to watch Short's king creep forward to help the queen deliver the final blow.

Nigel Short - Jan Timman
Tilburg (4) 1991

White has seized control of the d-file and the dark squares around Black's king. But how can he finish Black off? The queen cannot mate alone; White needs one more piece. The knight is immobile because of the mate threat at g2.

White could try to open up the kingside and bring a rook into the attack with a sequence like 31. Rd3 Rc8 32. R7d4 Rce8 33. g4. Then 33...hxg4 34. h5 gxh5 35. Qg5+ Kh7 36. Qxh5+ Kg8 37. Rxg4 is mate. (Other 34th moves for Black also lead to mate in this line, usually on g7 after White plays h6.) But Black can try 33...Qc5! 34. gxh5 Qe7, when White is still better, but there is no immediate win. Pawn-up endgames are not likely to lead to much for White, with his shattered queenside pawn formation.

Short's solution is brilliant: if the knight and the rooks cannot join the attack, he will use the only other piece available: the king!