1.e4 e5 2.Nf3 d6 3.Bc4 Be7 4.0–0 Nf6 5.d3 Nc6 6.h3 Na5

Black rids himself of white's stronger bishop.

7.Nbd2

But white consoles himself with the prospect of a knight posted on f5.

7...0–0 8.c3 Nxc4 9.Nxc4 Be6 10.Ne3 Qd7 11.Qc2 Nh5

Making for f4, after which black threatens to sacrifice on h3.

12.d4 Nf4 13.Nf5?!

Perhaps I can play pxe5 or d5 but I was worried about Bxh3.

13...f6?! 14.Bxf4 exf4 15.d5 Bf7?

I assume black wanted to retain his better bishop for a possible endgame, but the knight is too strong to be left here.

16.Qd2 g5? 17.Nxg5!

17...Bg6

The knight cannot be taken. After 17....Pxg5 18.Qd4, black has to give up his queen to prevent mate. 17..fxg5 18.Qd4 Bf6 19.Qxf6 Bg6 20.Nh6#

18.Ne6 Bxf5 19.Nxf8 Bxf8 20.exf5 Qxf5 21.Rfe1 Kf7 22.Qd4 h5 23.Qe4 Kg6 24.Qxf5+?

Better was Qf3

24...Kxf5 25.Re6 a5 26.Rae1 Ra6 27.Re8 Bh6 28.R8e7 Rb6 29.b3 c6 30.dxc6 bxc6 31.Ra7 Rb5 32.c4 Rc5 33.Rh7 Kg6 34.Rd7 d5 35.cxd5 cxd5 36.Rd1 Rc2 37.a4 Rc3 38.R7xd5 Rxb3 39.Rxa5 h4 40.Rb5 Ra3 41.a5 f3 42.gxf3

At this point black's bishop suddenly appeared on c3. I am ashamed to say I did not notice the illegal move.

(42...Bd2) 43.-- Bc3 !!!!!