Monday, October 26, 2009

J.Yoos vs L.Davies, Vancouver 2009






Today we will analyse an interesting ending from the game J.Yoos-L.Davies, played in the sixth round of this year's B.C. Championship tournament in Vancouver.

In the first diagram White is about to make his 39th move. Although White has the nominal advantage of bishop vs knight, Black's position does not present any cause for alarm. He is well-centralized and has the entry points under control. Indeed, White's bishop is somewhat short of targets, and will have to content itself with restricting Black's movements in the hope that his colleague the king can make something happen. But at the moment that does not look too likely.

39.Bf5 Ne8 40.Be4+ Kd6 41.Bg2 Nc7 42.Bb7 Ne8 43.Be4 Nf6 44.Bg6 Kc6

After some minor sparring we are back where we started. White tries a different tack.

45.Bf7 Kd6!?

After 45...a6 46.b5+ axb5+ 47.axb5+ Kd6 the draw could be agreed fairly soon.

46.Kb5 Ne4!?

This aggressive move suggests that Black is playing for a win, or at least keeping that possibility open. Otherwise he might have dug in with 46...Kc7 and if 47.Ka6 then 47...Kb8 48.Bg6 Nd5 49.Kb5 Kc7 50.Kc4 Kd6 51.Bf7 Nf6, when things are looking familiar.

It should be noted that at this point both players were running short of time. This largely accounts for the reversals of fortune that occur over the next few moves.

47.Ka6

White's only chance for active play is an attack on his opponent's queenside pawns. He could have prefaced this move with the interesting 47.g3!?, trying to prevent Black from creating a passed pawn, but then 47...Nc3+! 48.Ka6 Nxa4 49.Kxa7 Kc7 leads to yet another drawish position.

47...Nxf2 48.Kxa7 Kc7?

A serious error that should have cost Black the game. Correct was 48...Nd3! when there are two main variations:

A) 49.Kxb6 Nxb4 50.a5 e4 51.Bc4! (not 51.a6? Nxa6 52.Kxa6 e3 53.Bc4 Kc5 and Black wins) 51...e3 52.a6 Nxa6 53.Bxa6 Kd5 54.Ka5 h5 55.Kb4 Ke4 56.Be2 h4 57.g4 (or 57.gxh4 gxh4 58.Kc3 Kf4 59.Kd3 Kg3 60.Bg4 Kf2 and draws) 57...Kf4 58.Kc3 Kg3 59.Kd3 Kxh3 60.Kxe3 Kg3 61.Bf3 h3 62.Ke4 h2 63.Ke3 h1Q 64.Bxh1 Kxg4 with an immediate draw;

B) 49.b5 e4 50.Bg6! (other moves lose) 50...Nc5 51.Bxe4 Nxe4 52.Kxb6 Kd5 (not 52...Nxg3 53.a5 and White wins) 53.a5 Nd6 54.a6 Nc4+ 55.Kb7 Kc5 56.a7 Nb6 57.Ka6 Na8 and the draw is obvious.

(second diagram)

49.a5?

A serious error in return. White is perfectly placed to queen his b-pawn, needing only to lever Black's b-pawn out of the way. But he has to do it accurately. He should prevent Black's next move with 49.b5! when the likely continuation is 49...Nd3 50.a5 (only now!) 50...Nc5 (or 50...bxa5 51.b6+ etc.) 51.axb6+ Kd6 52.b7 Nxb7 53.Kxb7 and wins.

49...b5!

Correctly blockading the dangerous White b-pawn. Completely wrong would be 49...bxa5? 50.b5! as in the previous note.

50.Ka6 e4 51.Kxb5 e3 52.Bc4 Ne4 53.Bd3?

This is no time for waiting moves. White can still save the game with 53.Ka6! Kb8 (if 53...Nxg3 54.b5 e2 55.Bxe2 Nxe2 56.Ka7 Nd4 57.b6+ Kc6 58.b7 Nb5+ 59.Ka8 and Black must give perpetual with 59...Nc7+, etc.) 54.Kb6 Nc3 55.a6 e2 56.Bxe2 Nxe2 57.a7+ Ka8 58.g4 Nc3 59.b5 Na4+ 60.Ka6 Nc5+ 61.Kb6 Na4+ and again Black has nothing better than a draw.

53...Nxg3 54.Kc5 e2 55.Bxe2 Nxe2 56.b5 Nf4 57.b6+ Kb7 58.Kb5 (third diagram)

White's connected passed pawns give him a semblance of counterplay, but that's about it.

58...h5!?

Black wins cleanly after 58...Nxh3! 59.a6+ Kb8 60.Kc6 Nf4 61.a7+ Ka8 62.b7+ Kxa7 63.Kc7 Nd5+ 64.Kc8 Nb6+ 65.Kc7 Nd7! But the text move does not spoil anything.

59.a6+ Kb8 60.Kc6 Ne6?!

Black is afraid of the advancing White pawns and does not notice the winning knight manoeuvre. After 60...g4 61.hxg4 hxg4 62.a7+ Ka8 63.b7+ (if 63.Kc7 then 63...Nd5+ 64.Kc6 Nxb6, etc.) 63...Kxa7 64.Kc7 Nd5+ 65.Kc8 Nb6+ 66.Kc7 Nd7 Black wins easily.

61.Kd5 g4?

The final error, after which Black can no longer win. He can still transpose to the previous note with 61...Nf4+ 62.Kc6 Nxh3.

62.hxg4 hxg4 63.Ke4!

White's king correctly heads east in order to deal with Black's pawn.

63...Nc5+

Neither side can make progress and the draw was agreed here.

½–½




Thursday, October 15, 2009

Relative values


Anyone who studies a beginner's book on chess quickly learns that not all pieces have the same value. In my day the most common table of values went as follows: Pawn = 1 point; Knight = 3 points; Bishop = 3 points; Rook = 5 points; Queen = 9 points. Other tables have slightly different values for the bishop and the queen, but the overall ratios are very similar.

Based on this table, exchanging a rook for two minor pieces is considered advantageous because 6 points is more than 5 points. When such an opportunity arises it is a good idea to take a hard look at the resulting position and see if it is actually favourable. In chess it is not just the presence of pieces on the board that counts. Their location and relevant capabilities can be far more important.

I am playing Black in the diagram position and my opponent's last move was the weakening 20.g3-g4. I saw an opportunity to exploit this move by bringing one of my knights into an attacking position. There was an apparent drawback in that my opponent could give up one of his rooks for both of my knights, which according to the table would mean a net loss of 1 point. However in the resulting position there would be a strong manoeuvre available, one that my opponent had not foreseen.

20...Nge5! 21.Rxe5 Nxe5 22.Qxe5

So far, so good, thinks White; he has won two pieces for a rook.

22...a6!

This forces the White knight on b5 to an offside position and prepares to exchange off his colleague on d4. The preliminary pawn move is important because otherwise my opponent would maintain a knight on d4, giving him much better defensive chances.

23.Na3 Bxd4! 24.Qxd4

White could also play 24.cxd4 but then Black carries on with 24...Qxg4+ 25.Kf1 Qh3+ 26.Ke2 Re6, winning White's queen.

24...Qxg4+ 25.Kf1 Re8!

Also possible was 25...Qh3+ 26.Ke2 Re8+ 27.Kd1 Qf1+ 28.Kc2 Qxa1, but I preferred the text move, slamming the door on the opposing king. White has nothing better than 26.Qxd5+ Kh7 27.Qg3, but then follows 27...Qe2+ 28.Kg1 Rg6, a pleasing echo of the line in the previous note.

After a few minutes my opponent agreed he had no defence and resigned the game (0-1).

Sunday, October 11, 2009

Defensive tactics


Here is a late middlegame position of a type that arises so often in mixed tournaments. One side clearly has the initiative because of greater piece activity, but a decisive tactic has not quite materialised. In this particular case both players have pawn weaknesses but Black is on move and should be thinking about putting White to the test. But what's the best way forward?

This was the challenge facing Efim Geller (Black) in his game with Yuri Balashov from the 1969 Soviet Championship in Moscow. If it were White's turn to play, he would oppose rooks with 1.Re1 and take a large step towards neutralising Black's initiative. Geller understood this very well and was ready with an active idea:

1...Re2

The attack on the g-pawn makes things difficult for White, as the following variations show:

a) 2.Be1 Rxc2+ 3.Kxc2 Rxa2+ followed by 4...Rxg2 and Black wins easily;

b) 2.Rg1 Bd4 3.Re1 Rxg2, etc.;

c) 2.g3 Rf2 3.f4 (3.Re1 Rxf3) 3...b5 4.Re1 h5! 5.Re7 Rf1+! 6.Re1 Rxe1+ 7.Bxe1 h4 8.Kb1 ( 8.Rc5 Rxa2 9.Rxf5 Ra1+ 10.Kd2 b4–+) 8...Re4 9.Bd2 h3 and White is in continuing difficulties.

But there is a hidden resource that saves the game for White, and Balashov finds it:

2.Re1!! Rxg2 3.Rc8+ Kf7 4.Rc7+ Kf8

Unfortunately for Geller, Black can no longer play for a win. If 4...Kg6 5.Re6+ Kh5 and now White has the surprise shot 6.Rxg7!, which wins immediately because 6...Rxg7 runs into 7.Rh6#.

After the further moves

5.Rc8+ Kf7 6.Rc7+

the players agreed to a draw.

In the starting position Black has two other tries:

a) 1....Kf7 2.Re1 Rxe1+ 3.Bxe1 Be5 4.g3 f4, but White can defend with 5.gxf4 Bxf4+ 6.Kb2 Be5+ 7.Bc3 Rb4+ 8.Kc1 Bf4+ 9.Bd2 Ke6 10.Bxf4 Rxf4 11.Rc3;

b) 1...b5 2.Re1 Rxe1+ 3.Bxe1 Rc4 4.Rxc4 bxc4 5.Kc2 Kf7 6.g3 and a draw is the correct outcome.

The conclusion is that Black has a temporary initiative but no real advantage.

Despite his reputation as the scourge of world champions, Efim Geller had his hands full with Yuri Balashov, losing four games, drawing ten, and scoring just a single win against the Moscow grandmaster.


Thursday, October 8, 2009

Magnus goes astray



Judging from his current position near the top of the chess world, the Norwegian GM Magnus Carlsen doesn't make too many unforced errors. But an instructive counterexample occurred in his game with the Russian GM Peter Svidler from an international tournament in the Athens suburb of Kallithea in 2008.

In the first diagram, Magnus is playing White and is on move. Objectively, the most reasonable plan is to attack Black's g-pawn with 19.dxe6 fxe6 20.h4, bringing White's kingside pieces into action with the minimum of delay. But Magnus tries a different idea.

19.g3?

The idea behind this move is clear enough. White intends to mobilize his pawn majority with gain of time by attacking Black's bishop with f3-f4. But there is a flaw – a forcing variation that interrupts the smooth flow of White's game:

19...exd5 20.exd5 Bc2! 21.Rc1 Bg6

Things have obvously gone wrong for White, and no easy remedy is available. There are only two moves to keep White in the game. One is 22.g4, which is met simply by 22...Bxh5, and the other is the text move:

22.f4

Now if Black's bishop retreats from e5, White can protect his knight with 23.Be2.

22...Bxh5! 23.fxe5 Nd7! (second diagram)

As a result of the adventure inaugurated by 19.g3, White's pawn centre is now lifeless and exposed. At the grandmaster level one could regard Black's remaining task as a matter of technique.

The conclusion is that Magnus did not seek out Black's strongest reply when he decided on the move 19.g3? This represents a psychological failing that is far more common below the master level.

Friday, October 2, 2009

Fritz vs Fred


Fred, of course, is Fred Reinfeld. Fritz is our well-known German friend. Fred Reinfeld died in 1964, while Fritz wasn't “born” until 1992.

There is something of Fred in all human players. We don't see everything there is to see on the chessboard. Fritz doesn't either, but he's a machine – a machine that is tactically perfect within a certain range. Today we're going to turn him loose on one of Fred's annotations.

The diagram position comes from the game Tarrasch-Blackburne, Hastings 1895, and was annotated by Fred in his book Tarrasch's Best Games of Chess, published by Chatto & Windus in 1947. Blackburne is being attacked, and his last move was the reckless 26...g5. Tarrasch was ready:

27.Rxh6!

“A really elegant solution,” writes Fred. Fritz agrees, although he also points out that White can win with the prosaic 27.Bxg5 hxg5 28.Qxg5+ Kf8 29.b4! Na6 30.Bg6 Rd7 31.a3 Nc7 32.h4!, when Black is in a huge bind and cannot stop the march of White's h-pawn. A personal view perhaps, but I suspect that Siegbert Tarrasch's arch-rival Aron Nimzowitsch would have played the position this way.

27...gxh4?!

This loses in simple fashion, but what else can Black do? Fred points out that that White is mating by force after 27...Rxh6 28.Bxg5 Qc7 29.Bf6+! Very nice.

More stubborn was 27...Kxh6, and here is where things get interesting. Fred attaches one of his many exclamation marks to the move 28.Bxg5+, says that White wins, and begins to ramble on about Blackburne's poor handling of the French Defence. Fritz agrees that White can win after 28.Bxg5+, but shows that he must play accurately after 28...Qxg5!. Here is how the win is achieved: 29.Rf6+ Kh5 30.Qh3+ Qh4 31.g4+ Kg5 32.Qe3+ Kxg4 33.Rf4+ Kh5 34.Rxh4+ Kxh4 35.Qg3+ Kh5 36.Qf3+! Kh4 37.Qf6+ Kg4 38.Qg7+ Kf3 39.Kg1! (the star move, helping to close the net around Black's king) 39...Rxh2 (no better is 39...Bc6 40.Qg3+ Ke2 41.Qf2#) 40.Qf6+ Kg4 41.Qxd8 Rxc2 42.Qd1+ Kf5 43.Qxc2+ Kxe5 44.Qh2+ Ke4 45.Qe2+ Kd4 46.Qf2+ Kc3 47.Qxc5 and Black must resign. I don't think Fred saw any of this.

Instead of 28.Bxg5+, White has the more practical 28.Rf6+!? Kg7 29.Qxg5+ Kf8 30.Rh6!, leaving him with two extra pawns and an easy win after 30...Qxg5 31.Rxh8+ Qg8 32.Rxg8+ Kxg8 33.Bxd8. I found this myself, long before I met Fritz.

28.Rxh8

Now Black is getting mated no matter what he does, and therefore Blackburne resigned (1-0)


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.