Monday, April 27, 2009

Elements of a chess game

A chess battle - it is a battle unlike any other. There are moments in chess when one side of the board has a significant material advantage over the other, yet the supposed winning side is really about to lose. One side can still win even with less pieces. How can this be explained?

The qualities of chess consists mainly of a special role of the king. If a check is declared, the very first thing needed is to defend the king. At the same time, another piece can be attacked without excess consequences or counterattack. If there is no way to save the king from a check, then the game is over and it doesn't matter if either side had a better position. The special role of a king is best shown in the case of a stalemate, a perpetual check, or whatever.

Diagram #1
Paul Keres

White to move and mate in four:
We'll take a look at some examples. In Paul Keres' composition (above) black has the material advantage but white is expected to win because Black's king is weakly placed: 1.Bg5! Rf7 2.Bf4 Nc6 3.Bd2 and whatever move black makes will simply lead to 4.Bc3#, mate.

Diagram #2
White to move and draw:

In diagram #2 (above) white has three extra pawns but fortunately black is provided with a stalemate: 1.f6 Bxf6! 2.Kxf6=, stalemate.

Diagram #3
Shamkovich - A. Polyak

Leningrad, 1953
White to move and win (mate in two):

In the game Shamkovich - Polyak (above), it seems that black would have the advantage because of the passed pawns. Surprisingly though, white can deliver a checkmate in two: 1.Qxh6+ Kxh6 (or 1... Kg8 which leads to a mate by White's f-pawn with 2.f7# mate) 2.Rh3#.

During a castling attack it is often necessary to sacrifice pieces or pawns with the purpose to break down your opponent's pawn protection. Let's take the game Batuev - Abdusamatov for an example (diagram below). It is white to move and win: 1.Bxh7+ Kxh7 (or if 1...Kf8 then 2.Bh6!) 2.Bf6! Bxf6 (if the pawn captures the bishop with 2...gxf6, then white simply plays 3.Re3 and everything is downhill for black) 3.exf6.
Diagram #4
Batuev
- Abdusamatov

USSR, 1951
White to move and win:
In the position showed in diagram #5 (below) black had to force some exchanges in order to make the best of his weary position: 1...Rxf5 (or else a mate is enabled with 1...Bxg2 2.Ne7+ Kh8 3.Qxh7+!) 2.Rxf5 Qxe3+ 3.Kh1 Bxg2+ 4.Qxg2 Rae8 5.Qd5+ Kh8 6.Rf3, and in several moves white won the game.

Diagram #5
Kan - Abramowski
Leningrad, 1951
Can black play 1...Bxg2?:

Another important quality of a chess game is that of a pawn; it is able to promote to any piece, except for a king, of course. Let's take a look at diagram #6 (below): 1.Qg7! and black resigned because either way if 1...Rf8 2.Nf6+ or 1...Rxg7 2.hxg7.

Diagram #6
White to move and win:

In this next chess problem (diagram #7) we will quickly study a pawn endgame breakthrough technique: 1.b6! axb6 2.a6! Bb8 3.a7! Bxa7 4.c7 and in one move a queen promotion with 5.c8=Q.

Diagram #7

White to move and win:

In the last study of this post, we will look at the end of a game that was played by Samuel Reshevsky and Isaac Boleslavsky (diagram #8). The last move played was 1.R3d7? (the correct move was to play 1.Rd8), and now black had the opportunity to get away with a draw by playing 1...Ra7! with the idea of distracting the rook and promoting his own pawn. Interestingly though, both players missed this line.
Diagram #8
Reshevsky - Boleslavsky
Zurich, 1953
Black to move and draw:

Thursday, April 23, 2009

A trap in the Scotch Game

The Scotch Game is a great opening which any beginner could learn in order to avoid the complicated theory of the Ruy Lopez. It is not popular among master chess players but it should definitely be analyzed well through if one would like to get some tactful and interesting play.

Personally, the Scotch is one of my favorite openings because of its simplicity and the interesting middlegame and endgame positions which can arise. The main line of the Scotch Game goes as follows:

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Bc5 5. Be3 Qf6 6. c3 Nge7 7. Bc4 Ne5 8. Be2 Qg6 9. O-O

In the main line after 7. Bc4 Black equalizes the position with ...Ne5. Instead of playing 7. Bc4 there is an interesting minor variation which has not yet been discussed in great depth, which is to play 7. Nd2?

This is an indirect trap that White wants to set for Black which is to win a pawn. By playing this move White takes away one defender of his d4-Knight leaving it open for Black to snatch. Although, if Black ignorantly captures the under-protected Knight with 7...Nxd4, White simply plays 8. e5!

Black has overlooked that 9. cxd4 Bxd4 10. Nc4 attacks Black’s Queen while also adding a second predator to Black’s d4-Bishop. The Knight’s placement from d2 to c4 has unveiled the file-power of White’s Queen. Black loses his dark-square Bishop.

With correct play, White should lose a pawn in this variation, since moving his Knight from b1 to d2 weakens White’s control over d4. After 8. e5, Black should give up the idea of 8...Qxe5? in favor of 8...Nc2+ . White takes the intruding Knight, 9. Qxc2, which allows Black to capture the King-pawn, 9...Qf6xe5. With careful play, Black should hold on to his additional pawn and get the advantage, but Black fell asleep at the board. Black cordially captures the e5-pawn, possibly never considering White’s reason for the sacrifice. If he had, he might have realized that White’s e4-e5 advance was not a sacrifice but a trap.

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Bc5 5. Be3 Qf6 6. c3 Nge7 7. Nd2 Nxd4 8. e5 { If Black captures with 8...Qxe5? then White plays 9. cxd4 winning a bishop. Blacks safest move instead of capturing the e5-pawn is to play 8...Nc2+. White is forced to capture with 9. Qxc2. } 8... Nc2+ 9. Qxc2 Qxe5 10. Nc4 Qe6 11. Be2 Bxe3 12. Nxe3

Copyright © 2009 Dave's Chess Blog

Stalemate To Whose Favor?

The question stated in the title seems a bit strange, doesn't it?

Everybody nowadays knows that stalemate is an equal ending from which no side gains or loses. A half point to me, a half point to you.

And here we are asked: "to whose favor?". To nobody's!

Below is an endgame position that was reached in a game played in Moscow 1961, the chess players being one of the strongest that the Soviet Union once had at the time - grandmaster David Bronstein (white pieces) against grandmaster Ratmir Kholmov.

White to move:

As shown in the diagram, a draw is forced after 52. Rc2+ Kb3 53. Rc3+ Kb2 54. Rc2+ or the also more aggressive line of cleaning the board as fast as possible - 52. Rb7 a2 53. Rxb5+ Ka1 54. Ra5 Kb2 55. Rxa2+.

Sources

ChessGames Chess Database & Community. <http://www.chessgames.com/perl/chessgame?gid=1034134>.

Copyright © 2009 Dave's Chess Blog

Monday, April 20, 2009

Cunningham Gambit

One of the simpler variations of the King's Gambit is the less common Cunningham Gambit: 1.e4 e5 2.f4 exf4 3.Nf3 Be7 4.Bc4 Nf6. After 4.Bc4 or 4.Nc3, Black could choose to play ...Bh4 giving a check and preventing White from castling. Either way, the results can become hard and complex to evaluate for beginning and advanced players. The problem with playing 4...Bh4+ is that it leaves the bishop hanging for a possible pawn counterattack from White. This tactic of breaking through White's defenses with a barrage of bishops and pawns was unsuccessfully tried in a game by Henry Bird, playing the Black pieces, against Paul Morphy:

Morphy - Bird [C35]
London 1859
King's Gambit: Accepted. Cunningham Defense Bertin Gambit 1-0

1.e4 e5 2.f4 exf4 3.Nf3 Be7 4.Bc4 Bh4+ 5.g3 fxg3 6.O-O gxh2 7.Kh1 d5 8.Bxd5 Nf6 9.Bxf7+ Kxf7 10.Nxh4 Re8 11.d3 Bh3 12.Qh5+ Kg8 13.Rxf6 gxf6 14.Nc3 Re5 15.Qf3 Qd7 16.Bf4 Nc6 17.Kxh2 Bg4 18.Rg1 h5 19.Bxe5 fxe5 20.Nd5 Nd4 21.Nf6+ Kh8 22.Qe3 Qg7 23.Nxh5 Qh7 24.Rxg4 Qxh5 25.Qh3 Kh7 26.c3 Ne6 27.Rg6 Re8 28.Rxe6 Rxe6 29.Qxe6 Qxh4+ 30.Qh3 Qxh3+ 31.Kxh3 c5 32.Kg4 Kg6 33.Kf3 Kf6 34.Ke3 Ke6 35.d4 exd4 36.cxd4 cxd4 37.Kxd4 Kd6 38.e5+ Ke6 39.Ke4 Ke7 40.Kd5 Kd7 41.e6+ Ke7 42.Ke5 a6 43.a3 Ke8 44.Kd6 Kd8 45.e7+ Ke8 46.Kc7 1-0

Chess masters in the early twentieth century painstakingly examined numerous positions that arise from this unique gambit with unfinished results. In his 1932 chess manual, Emanuel Lasker wrote:

"The Cunningham Gambit has gone wholly out of fashion." (page 65)

And it sure has. Popularity graphs for this gambit have shown a dramatic decrease starting at the end of the eighteenth century, when the Cunningham Gambit was first introduced, just up to the 1970s when the last peak of this gambit was shown. Fashion changes and so it does in chess. New generations of players means new ideas and styles. Perhaps maybe one day the chess world will see this fancy gambit once again in action.

Sources

Chess openings: King's Gambit Accepted, Cunningham (C35). 2004.
20/20 Technologies. 08 April 2009. .

Lasker, Emanuel. Lasker's Manuel of Chess. New York: Courier Dover
Publications, 1960.


Copyright © 2009 Dave's Chess Blog