Sunday, March 18, 2007


Last time we looked at some interesting play from the 2006 B.C. Championship and today there is more on the menu. The game McLaren-Wu reached the first diagram after several moves of a Fianchetto Grunfeld. The position is absolutely symmetrical with the important proviso that it is White's move. It has been understood for many years that maintaining symmetry can be an effective equalising strategy for Black as long as he realises that a moment will come when the symmetry must be broken. In the present game this moment arrives after White's next move:
If Black now plays 9...Ne4?! there follows 10.Nxc6 and he cannot continue with 10...Nxc3 because of the line 11.Nxd8 (also possible is 11.Nxe7+ followed by 12.bxc3 but capturing the queen is stronger) 11...Nxd1 12.Nxf7 Nxf2? (the lesser evil was 12...Rxf7 13.Rxd1 leaving White a solid pawn ahead) 13.Nh6+ Bxh6 14.Bxh6 and White wins the exchange after 14...Nh3+ 15.Bxh3 Bxh3 16.Rxf8+, incidentally breaking the symmetry in decisive fashion. Therefore Black must find a more effective way. As in the Exchange Slav a key question is whether capturing on c6 and transforming Black's b-pawn into a backward c-pawn constitutes a positional threat. On the one hand this pawn could be a handy target for White's pieces; on the other hand it might be difficult to attack or even blockade the pawn without allowing counterplay on the central dark squares. These ideas would take concrete form in the sample line 9...Bf5!? 10.Nxc6 bxc6 11.Bf4 Nd7!? threatening to obtain complete freedom with 12...e5. In the game Black apparently decided that 10.Nxc6 was a threat so he took the decision to capture on e5 himself:
9...Nxe5 10.dxe5 Ng4
Countering White's attack on the d-pawn with his own attack on the front e-pawn.
Also possible was 11.Qxd5 since exchanging queens loses a pawn for Black and 11...Nxe5 12.Qc5! gives White a small but definite advantage on account of his more active pieces, the disparity between the two light-squared bishops being especially striking.
11...e6?! (second diagram)
It appears that Black did not like the variation 11...Nxe5 12.Bg5! Nc6 13.Rc1 (threatening 14.Rxc6!) but in fact the resource 13...Be6! would solve most of his problems. Now 14.Rxc6 is met by 14...Bxd5! 15.Rc2 Bxg2 16.Kxg2 Qa5 17.Bxe7 Rfe8 18.Ba3 Rad8 and Black's active pieces give him excellent compensation for the pawn. In the actual game White now played 12.Nf4?! and after 12...Nxe5 13.Qb3 Qa5! Black had largely equalised the chances. What interests us here is what would happen after the desperado move
At first glance this looks pointless because multiple captures on f6 will leave an almost symmetrical position with little opportunity for either side to play for an advantage. This is seen clearly in the lines 12...Nxf6 13.exf6 Bxf6 or 12...Nxf6 13.Qxd8 Rxd8 14.exf6 Bxf6. But in the latter variation White has an effective zwischenzug:
12...Nxf6 13.Qxd8 Rxd8 14.Bg5!
Black's knight is pinned against his rook, so he must acquiesce to the loss of a pawn. The main variations are in White's favour:
a) 14...Bd7 15.exf6 h6 (15...Bh8 and 15...Bf8 are both met by 16.Rac1) 16.Bf4 Bxf6 17.Bxb7, winning the exchange;
b) 14...h6 15.Bxf6 Bxf6 16.exf6 e5!? (not 16...Rd2 17.Rfd1 Rc2 18.Rd8+ Kh7 19.Rf8 Rc7 20.Rad1 and wins) 17.Rfd1 Bg4 18.Kf1! Rab8 19.Rac1 b6 20.Ke1! Rxd1+ 21.Kxd1 Rd8+ 22.Ke1 Rc8 23.Rxc8+ Bxc8 24.Bd5! and Black is in great difficulties because of his weak f-pawn.

Let's peel back to the position after 12.Nf6+!? and take a look at the alternative:
This cannot be satisfactory because it gives up the natural defender of the dark squares around Black's king.
13.exf6 Qb6!?
Or 13...Qxf6 14.Qa4 Qf5 (and not 14...Ne5 15.Rd1 Rd8 16.Rxd8+ Qxd8 17.Bf4 Nc6 18.Rd1 Qe7 19.Bd6 Qe8 20.Qh4! and White has a winning attack) 15.Qh4 e5 16.Rd1 Qe6 17.Bh6 Re8 18.Rd2 with advantage to White.
14.Qa4 e5 15.b3 Nxf6 16.Be3 Qe6 17.Rfd1 Re8
Stronger than 17...Bd7 18.Qh4!
18.Bg5 Kg7 19.Rac1
White has an obvious advantage. Black's queenside remains undeveloped and under pressure from White's active pieces.

The actual game ended in a draw after some further adventures.

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Port Coquitlam, British Columbia, Canada
National master (Canada) since 1984. B.C. Champion 1977 and 1984. Runner-up 1991 and 2002. B.C. Open Champion 1972 and 1982. B.C. U/14 Champion 1964-65-66. Mikhail Botvinnik once wrote that publishing your analytical work forces you to be accurate because it exposes you to criticism. Hence this blog.