US Championship Round 2 Annotations
May 23, 2009 • General
Jaan Ehlvest (2606) – Hikaru Nakamura (2701) US Championship, Saint Louis 9.5.2009
1.Nf3 Nf6 2.c4 e6 3.g3 b6 4.Bg2 Bb7 5.0-0 Be7 6.b3 0-0 7.Bb2 d5 8.e3 c5 9.Nc3 Nc6!? (Diagram 1)
This pretty much the starting position for the whole variation. However, despite being roughly equal, 9…Nbd7 was slightly easier to play.
10.cxd5 Nxd5 11.Nxd5 Qxd5 12.d4 Rad8 13.Ne5 (Diagram 2)
The past few moves have all been standard theory. However, here I slightly lose my head and played 13…Qxg2?! (13…Qd6 was slightly more sound. After 14.Qe2 Nxe5 15.Bxb7 Bf6 White is slightly better, but the position isn’t particularly anything special. Another try is 14.Nd7 Qf5 15.e4 Qg5 16.h4 Qh6 17.Bc1 g5 with an unbalanced position. (Diagram 3)
However, the game continued as follows. 14.Kxg2 Nxe5 15.f3 cxd4 16.exd4 (not 16.Bxd4 Nxf3! 17.Rxf3 e5 after which Black has no problems.) 16…Nc6 17.Qe2 Rd5 18.Rac1 Rfd8 (Diagram 4)
Here, I have achieved the basic setup which I envisioned when I first decided to sacrifice my queen. When I saw this position in my analysis, I simply did not see how White could progress with sacrificing an exchange somewhere. I figured that I will always have Bf6, Nxd4 ideas or even g5-g4 plans creating discoveries along the long diagonal. Unfortunately for me, Ehlvest remained calm under pressure and found the best “human” move.
19.Rc4! Ba6 (All other moves are bad. For example, 19…Bf6 20.Qf2 Nxd4 21.Rc7 Ba6 22.Rd1 and White is clearly winning. 20.Qe4 Bxc4 21. bxc4 R5d6 22.Rd1 Bf6 23.Ba3! Rxd4 24.Rxd4 Nxd4 (Diagram 5)
The last set of moves have been more or less forced. Ehlvest has done a good job to this point as he has simplified and retains good winning chances. 25. Bc1!? (According to the computers, 25.Qb7 g6 26.Qxa7 Nc2 27.Bc1 Ne1 28.Kh3 Nxf3 29.Qxb6 h5 30.c5! is winning. However, it is hard to blame a human as this looks quite dangerous due to g5-g4 Rd1-g1 threats or Rd1 and Rh1 ideas too.) 25…h5 26.g4! (Now 26.Qb7 would be a lot less effective after 26…Nf5 27.Qxa7 Rd1 28.Qa3 Be7 29.Qc3 Bc5.) 26…hxg4 27.fxg4 g5 (Diagram 6)
This is the critical position. If Jaan had played 28.h4! gxh4 29.Qf4! Bg7 30.Qc7 he would have had excellent winning chances. After the text move, I am able to set up a fortress more or less regardless of what he does. 28.Be3?! e5 29.a4 Rc8 30.Qd5 Ne6 31.Kf3 Be7! (Giving a pawn back, but setting up an inpenetrable fortress.) 32.Qxe5 Rxc4 33.Qb8 Kg7 34.Qxa7 Bd8 (Not 34…Bc5 35.Bxc5 Nxc5 36.Qxb6 Rf4 37.Kg3! Nxa4 38.Qd8! and Black is simply losing.) 35.Qd7 Rb4 36.h3 Bf6 37.Qd1 (Diagram 7)
White cannot make any progress here, same as Black. Had Jaan not offered a draw, the simplest way to force a draw is 37…b5 38.axb5 (38.a5 Ra4 39.Bb6 [39.Qe1 b4=] 38…Rxb5 with complete equality.