Expose the King!

In a recent correspondence game, I found a single reference game in which Black's play struck me as a bit timid.

Black to move

My database contains six games that reached this position, one with White to move. I only looked at those games played by masters (ratings above 2200). The highest rated Black player continued with 10...Ne5.

10...Bd6 was played in the other two games. White must address the threat to h2.

11.f4

My opponent threatened e5, following one of my reference games.

11.g3 was attempted in the other reference game. That did not go well for White. 11...Bxg3 12.hxg3 Qxg3 13.Kh1 Ne5 14.Nc5 Nfg4! 15.fxg4 Qh3+ 16.Kg1 Qxe3+ 17.Rf2 Qxc5 and White resigned after two more moves. Brynjarsson -- Bjornsson, Reykjavik 2009.

11...b4

I studied the remaining reference game, and noticed that Black gained an attack on the king. Black's attack faltered, but need not have done so. Initially, Black seems to sacrifice a knight but gains three pawns for the piece. Another sacrifice, however, this time for a single pawn fatally exposes the White king. This second sacrifice was not played in the reference game.

12.e5

The fork.

12...Nxe5

Beginning a tactical operation that exchanges a knight for three pawns and leaves the White king exposed.

13.fxe5 Bxe5 14.Nb1N

The reference game continued: 14.Na4 Bxh2+ 15.Kh1 Qg3 (15...Bxg2+! 16.Kxg2 Qg3+ 17.Kh1 Qh3 18.Rf2 Bf4+ 19.Kg1 Bxe3 and Black has recovered the material with interest.) 16.Bf3=  and the game was drawn in 42 moves. Toubale,T -- Villeneuve,A (2345), Cannes 1989.

14...Bxh2+ 15.Kh1 

Black to move

I had been aiming for this position.

15...Bxg2+! 

As seen in the reference above, 15...Qg3 gives White time to organize a defense.

16.Kxg2 Qg3+ 17.Kh1 Qh3

White to move

18.Rf3

18.Rf2 is better 18...Bf4+ 19.Kg1 Bxe3 20.Qf1 Qg3+ 21.Qg2 Bxf2+ 22.Kf1 Ne4–+.
18.Rxf6 fails. 18...Bg3+ 19.Kg1 Qh2+ 20.Kf1 Qh1+ 21.Bg1 Qh3#.

18...Bg3+ 19.Kg1 Qh2+ 20.Kf1 Qh1+ 21.Bg1 Qh3# 0–1

Finding the decisive blow was almost certainly helped by my having read earlier this summer several of Mihail Marin's recent columns for Chess Informant. In particular, for Informant 122 he wrote, "Is Chess a Matter of Memory? Lasker's Double Bishop Sacrifice."