White: GM Dimitry Gurevich
Black: Peter Bereolos
Chicago Open, 2000
Round 6 Board 10
1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5 7.0-0 Na6 8.Re1 Bg4
This is a common move in the ...Na6 systems (one of the points of Na6 instead of Nbd7 is that the bishop is not blocked) but usually Black waits until White has retreated his bishop to f1 so that there is more pressure on the d4 square
9.d5 Nc5 10.h3 Bxf3 11.Bxf3 a5 12.b3 Nfd7 13.Rb1 f5 14.a3 Nf6 15.exf5 gxf5 16.b4 axb4 17.axb4 Ncd7 18.Be2 Ne8 19.Qc2 Qh4 20.Bf1 Kh8
The immediate 20...c6 is probably better. It isn't clear at this point that the Black king will be safer on the a1-h8 diagonal than on the a2-g8 diagonal.
21.Bb2 c6 22.dxc6 bxc6 23.Rbd1 e4 24.c5
I saw the upcoming piece sacrifice, but didn't quite believe it. The more thematic 24.b5 may be better.
Otherwise, White has very little. For compensation, White gets two strong passed pawns and tries to take advantage of the scattered nature of Black's forces.
25...cxd5 26.Rxd5 Qe7 27.c6 Nb6
This move looks natural, blockading the pawns, but I overlooked his strong maneuver Rd5-b5-b7. Better was 27...Ne5 or 27...Ndf6 when 28.Rb5 can be met 28...Nd6. So he has to go 28.Rc5 when Black has better chances to organize a defense. After the text, White is able to gain several tempi.
[28... Rb8 29.Qc5]
29.Rb7 Nc7 This is probably the decisive blunder since now b6 will come with tempo, too. 29...Qe6 is a better try.
30.b5 Nd6 31.b6 Nxb7 32.cxb7 Ne6 33.bxa8=Q Rxa8 34.Bxg7+ Kxg7 35.Qc6 Rd8 36.Ra1 Nd4 37.Qc7 Qxc7 38.bxc7 Rc8 39.Rc1 Ne6 40.Rc6 Nxc7
Losing the exchange, but guarding the knight fails to Bc4 when there is a pin either along the rank or along the diagonal.
41.Ba6 Nxa6 42.Rxc8 Nb4 43.g4 fxg4 44.hxg4 Nd5 45.Rc4 Nf6 46.g5 Nh5 47.Rc6 Nf4 48.Kh2 Ne2 49.Kh3 Nd4 50.Rf6 Nf3 51.Rxf3 exf3 52.Kg3 Kg6 53.Kg4 h6 54.gxh6 Kxh6 55.Kxf3 Kg5 56.Ke4 1:0