My opponent was Pete Dyson of Florida.

1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.Qc2 c5 5.dxc5 Na6 6.a3 Bxc3+ 7.Qxc3 Nxc5 8.b4 Nce4 9.Qb2 d5 10.c5 d4 11.e3 e5 12.f3! Nc3 13.Bd2 Nfd5

Game position after 13...Nfd5

See Morss-Dolgitser for a discussion of alternatives. Black's move is challenging, and I carefully considered it before I played 12. f3. Not quite carefully enough, however.

14.e4 Nxe4 15.Bb5+ Bd7!

15...Kf8 16.fxe4 Qh4+ 17.Kf1 Qxe4 18.Re1 Qf5+ 19.Nf3 f6 20.Kf2 and Black does not have enough for his piece.

16.Bxd7+ Qxd7 17.fxe4 Qg4

Game position after 17...Qg4

The critical position of the game.

18.Ne2!

It was fortunate for me that this resource turned up after 17...Qg4 had been played. The move I had planned to play when originally analyzing 12. f3 turned out to be unsatisfactory.

18.Kf1 Qxe4

A) 19.Re1 Qd3+ 20.Kf2 e4 21.Nf3 e3+ 22.Kg1 0-0-0 23.Bc1 Nc3 and Black has what seems to be sufficient compensation for his piece.;

B) 19.Qb3 0-0-0 20.Re1 Qf5+ 21.Qf3 Qc2 22.Re2 d3 23.Rf2 (23.Qf5+ Kb8 24.Qxe5+ Ka8 25.Rf2

Analysis position after 25. Rf2

25...Ne3+!! 26.Qxe3 Rhe8 27.Qxe8 Rxe8 28.g3 Qb3 29.Kg2 f6 30.Nf3 Qxa3 31.Re1 Qa4 and Black's Queen and pawns seem to be a match for White's Rook and two minor pieces ) 23...e4 with compensation;

C) 19.Nf3 0-0-0 20.Re1 Qd3+ 21.Kf2 e4 22.Nxd4 (22.Qxd4 Nf6! and Black equalizes ) 22...e3+ 23.Rxe3 (23.Bxe3 Nxe3 24.Rxe3 Qxd4 25.Qxd4 Rxd4 with equality ) 23...Nxe3 24.Bxe3 Rhe8 25.Re1 Rxe3 26.Rxe3 Qxd4 27.Qxd4 Rxd4 with equality;

18.Kf2 When I first analyzed 12. f3, and even after I received my opponent's card with 17...Qg4, I thought that this would be my move. I even filled out a card with this move on it before I noticed Black's best response; 18...Nf6! Black thus wins the e-pawn and regains his tempo, after which his mobile central pawns offer good compensation for the lost piece. 19.Nf3 Nxe4+ 20.Kg1 (20.Kf1 f6 is not too comfortable for White either, one amusing thought being 21.Qb3? Qxf3+!) 20...0-0-0!

Analysis position after 20...O-O-O!

A) 21.c6 Nxd2 22.Qxd2 e4 23.h3 Qg3 24.Qg5 (24.Nxd4 e3 25.Qb2 Qe5 is good for Black ) 24...Qxg5 25.Nxg5 Rhe8 26.Nxf7 Rd5 27.cxb7+ Kxb7 leaves Black with excellent compensation for his piece, for example 28.Kh2 e3;

B) 21.Nxe5? Qe2;

C) 21.Rc1 Rhe8 22.c6 Nxd2 23.Qxd2 e4 24.h3 Qg3 25.Nxd4 e3 26.Qb2 Qe5 and I prefer Black.

18...Qxg2

18...Qxe4 19.0-0! Qxe2 20.Rae1 and White returns his piece for a dominating position.

19.Ng3 Ne3

19...Nf4 20.Qb3 followed soon by O-O-O and White is winning.

20.Qb3

In the entire line with 12. f3, I discovered, this little redeployment is thematic.

20...0-0-0 21.Ra2!

A nice way to sweep Black's queen out of White's position.

21...Qf3 22.Bxe3 dxe3 23.Rf1 Qg4 24.Rxf7!

White has no further reason to be nervous.

24...h5 25.c6! h4 26.cxb7+ Kb8 27.Qc2 Rd7 28.Rxd7 Qxd7 29.Nf5 Kxb7 30.Qc5 Rd8 31.Nxe3 1-0

The losing move was 13...Nfd5.