13 November 2007

Watson's Example Exchange Sacs

A resource complementing Petrosian's Exchange Sacrifice, is a chapter in John Watson's Secrets of Modern Chess Strategy, titled 'The Exchange Sacrifice'.

It is instructive to search pre-1930 databases for successful exchange sacrifice. Almost without exception, we find compensation only from direct mating attacks and/or the immediate acquisition of at least two Pawns for the exchange. Long-term sacrifices are seldom seen; one feels that this simply must reflect a pre-modern attachment to static material evaluations. There are nevertheless a few precursors of the modern attitude. Tarrasch himself, in annotating a game between Janowski and Lasker from 1909 (won by Janowski, the exchange down), commented that a Knight in the middle of the board, protected by a Pawn and out of the range of any enemy Pawn, is nearly as strong as a Rook.

The Lasker - Janowski game was played in the May 1909 non-title match to determine if Janowski was a worthy challenger for a title match. The four game match ended tied with two wins each and the two players met again in a longer match in October, although still not for the title. The exchange sacrifice starts from the position shown in the diagram.

Janowski [Janowsky] played 47...Qh6, which looks like a blunder. White wins the exchange with 48.Ng4 Qh7 49.Ngxf6+ Rxf6 50.Nxf6+ Rxf6.

Paris, May 1909, Game 2
Janowski, David

Lasker, Emanuel
(After 47.f4-f5)
[FEN "5rk1/2p2r2/p1Pp1bq1/1p1PpP1p/1P1nN3/3RN1PQ/P7/3R3K b - - 0 47"]

The game continued 51.Rf1 Qf7 52.Qg2 Rxf5 53.Rxf5 Qxf5, when Black had recovered one Pawn for the exchange. A few moves later Black also won the b-Pawn, but had to sacrifice the h-Pawn to keep the files closed on the Kingside. Black eventually forced a passed Pawn on the Queenside by trading a pair of Pawns on the a-/b-files. After the Queens were swapped off, the Rook was unable to cope with the Knight and passed Pawn. To play through the complete game see...

Emanuel Lasker vs David Janowski, Paris 1909
http://www.chessgames.com/perl/chessgame?gid=1064704

...on Chessgames.com. Watson used five of Petrosian's examples and added 12 of his own:-

1921 Triberg, Selesniev - Alekhine
1922 Teplitz-Schonau, Treybal - Spielmann
1945 USSR Chp, Tolush - Botvinnik
1943 Moscow, Ljublinsky - Botvinnik
1943 Moscow, Panov - Simagin
1950 Moscow, Bondarevsky - Mikenas
[Petrosian games]
1991 Wijk aan Zee, Seirawan - Kozul
1960 Leipzig, Gligoric - Tal
1981 Moscow, Beliavsky - Kasparov
1993 Linares, Karpov - Gelfand
1983 Barcelona, Martin Gonzalez - Dolmatov
1996 Dos Hermanas, Ivanchuk - Kramnik

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