Chess

If at all possible, you should always try to play the move that your opponent's last move was intended to prevent. It may be worth it for the shock value alone, but also the positional damage can be enormous when a move designed to prevent something turns out not to have the desired effect.

The diagram position comes from the game McNab-Wilson, played in the 4 Nations Chess league last weekend. Black had just played 14...g6, keeping the white knight out of f5 and also stopping White's g-pawn from advancing to g6 itself.

That, at least, was the intention, but the Scottish grandmaster playing White continued 15.Nf5! gxf5 16.g6! combining both moves that had supposedly been prevented. However, the sacrifice is by no means clearly correct. White can calculate as far as 16...hxg6 17.Rxg6+ Ng7 (17...Kf8 18.Bh6+ or 17...Kh7 18.Rh6+ are clearly bad for Black) 18.Rdg1 Be5 19.exf5 Nf8 20.Rh6, but after that it is not easy to be sure that White's queen can reinforce the attack at h3 before Black can summon up some counter-play. As the game went, Black managed to block the a2-h7 diagonal long enough to force White to invest a whole rook in his attack, but once the diagonal became open again, Black could only buy time at the cost of large material loss.

A good game by McNab whose tricky move-order in the opening seemed to lure his opponent into a variation with which he was not familiar. Black could have secured a comfortable position with 4...g6 instead of 4...e6, while 9...Re8 is a serious waste of time. If he is going to play dxc4 and e5, he should do so at once, keeping the rook on f8.

White: Colin McNab

Black: John Wilson

Semi-Slav Defence

1 c4 c6 17 Rxg6+ Ng7

2 Nf3 d5 18 Rdg1 Be5

3 e3 Nf6 19 exf5 Nf8

4 Qc2 e6 20 Rh6 b5

5 d4 Nbd7 21 Bb3 b4

6 Nc3 Bd6 22 Na4 c5

7 Bd2 0-0 23 Qd3 c4

8 0-0-0 Qe7 24 Qh3 Ng6

9 Rg1 Re8 25 Rgxg6 fxg6

10 g4 dxc4 26 Bxc4+ Be6

11 e4 e5 27 fxe6 Nh5

12 g5 Nh5 28 Rxg6+ Bg7

13 Bxc4 exd4 29 Qxh5 Rac8

14 Nxd4 g6 30 b3 Qb7

15 Nf5 gxf5 31 Bh6 Qh1+

16 g6 hxg6 32 Qd1 resigns