Wednesday, April 18, 2007


One of my tournament games from a few years ago featured a positional sacrifice of two minor pieces for a rook and two pawns. Working with the added advantage of more active pieces I managed to grind down my opponent and score a fairly convincing victory.

While analysing the game later on I found a much nicer continuation that had completely escaped my notice during play. I don't quite know how to characterise it, so I've taken advantage of that wonderful convention of the German language and coined the term zwischenkombination. Experienced chess readers will no doubt grasp the intended meaning: an in-between combination; or in other words, a combination in the middle of another combination.

In the first diagram I am playing Black and my last move was the liberating 23...c5! My opponent's position is now somewhat worse but probably defensible with best play. Happily for me he makes a mistake.
Before executing a move it can be useful to ask oneself how it changes the position. Decentralising moves are especially risky because they tend to leave key squares undefended. Black takes immediate advantage.
24...Bxe4! 25.fxe4 Nxe4 26.Qe1 (second diagram)
Black's next move regains material and is thematic, obvious, and... not the best!
Have a look at the intermediate combination that starts with the move 26...Nxc2!! It turns out White is in a very bad way no matter what he does; for example: 27.Rxd7 Rxd7 (not 27...Nxe1? 28.Rxc7 Rxd1 29.Rxe7 Rxb1 30.Nxc5 and White is actually better) 28.Rxd7 Qxd7 29.Qc1 Ng3+! (and not 29...Nxe3 30.Qxe3 Qd1 31.N1d2 with some defensive chances) 30.Kg1 Nxf1. With this move Black regains the piece and remains at least two pawns up. In missing this possibility I did not perceive that eliminating White's c-pawn would leave his knights undefended, in particular the one on b3.
After 26...Nxd2 the game continued:
27.Rxd2 Nf5 28.Qf2?!
Of course White should not surrender his dark-squared bishop so readily. I had analysed 28.Bf2 c4 29.Rxd7 Qxd7 30.N3d2 Bg5 31.Ne4 Qd1 and assessed it as better for Black, which seems fairly accurate.
28...Nxe3 29.Qxe3 c4 30.Rxd7 Rxd7 31.N3d2
And now for some reason I rejected 31...f5! 32.Nf3 e4 33.Nd4 Bc5 34.c3 but of course in this variation 34...Qe5! is easily winning for Black. Instead I played 31...Bc5?! but still won after a further 20 moves. Chess is a difficult game.

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About Me

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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.