GMChess Review: A. Khalifman, O. Biriukov. Opposite-coloured geometry lesson

Opposite-coloured geometry lesson!

A. Khalifman, O. Biriukov.

A curious ending arose in the J.Polgar - V.Kramnik game of the 7th round in Wijk aan Zee. During on-line translation ICC was aboil with controversy. The question was: "Will Black win or it will be a draw?" But neither the participants of this game nor leading chess players have expressed their opinion on the point after the game.A curious ending arose in the J.Polgar - V.Kramnik game of the 7th round in Wijk aan Zee. During on-line translation ICC was aboil with controversy. The question was: "Will Black win or it will be a draw?" But neither the participants of this game nor leading chess players have expressed their opinion on the point after the game.

Diagram 1.
(After the 71th White's move.)

71...Rd2!

A crucial position. Black's pieces are situated on the best squares. Now Black forces a bishop ending where his king will have a possibility to get white pawns via queenside. Note that White must keep his rook on d3. If not the d5-pawn would be lost. And there are no any other reasonable moves except rook's exchange. That's zugzwang.

72.Rxd2 exd2

The passed pawn changed the file (it is on the d-file now) and it came nearer to the queening square. Black with his next moves will be forced to protect the d1-square not only by the bishop but by the king also.

73.Bd1 Kb6 74.Ke2

Diagram 2.

74...Ka5?

At this moment thre were not more than 10 min. on the V.Kramnik's clock. So he had made a mistake which helped White to save the game. Yes, Black's move is understandable if you are a human player. Black king goes to d2-pawn's aid via black squares avoiding unacceptable White's surprises. But there is no rule without an exception. In this case it was necessary to put the king just on the white square: 74.Kb5! The thing is that the king is 1 move nearer to the d5-pawn (in distinction from the text move). And the d5-pawn is a potential target for black pieces. We'll consider bellow what would happen after 74. Kb5! But now let's see how White managed to draw after a5.

75.Bc2!

White is preparing a breakthrough g3-g4 on the kingside trying to do away with his weak pawns with a minimal loss.

75...Bg1

Black is going to put his bishop on h2 with the idea of destruction white pawns on the kingside. It seems White's previous move mistake cannot be corrected. After 75...Kb4 76.Kxd2 (White should not be at a stop because after 76.Bd1 Bg1 77.Bc2 Bh2 78.Kf2 Kc3 79.Ba4 Kb2-+ Black will win easily extending the defensive of White.) 76...Bf2 77.g4 hxg4 78.h5 gxh5 79.Bxf5 Kc5 80.Ke2 Bd4 (the same position arises after 80...Bg1 81.Bg6 h4 82.Bf5 g3 83.Be6 Kd4 84.Kf3=) 81.Be6 Bf6 82.Bf7 h4 83.Be6 g3 84.Kf3 Kd4 85.Bf7 Bd8 86.Be6 Ba5 87.Bf7 Be1 88.Be6 Bf2. And though White is in zugzwang he can keep the position due to his passed f-pawn.

Diagram 3.

Playing 89.Bh3! (White can't keep his bishop on the a2-g8 diagonal because after 89.Bf7 89...h3 90.Be6 h2 91.Kg2 Ke4 92.f5 h1Q+ 93.Kxh1 Kf3-+ Black wins. In case of 89.f5 after 89...Ke5 90.Kg2 Bb6 91.Kf3 Bd8 92.Kg2 Kf4-+ Now, if White wants to get back the control under the c8-h3 diagonal he must give the "f" pawn. But it is unacceptable to him. The same thing would happen after 89.Kg2 Ke4 90.f5 Ke5-+) 89...Kxd5 90.Kg4 Kc5 91.Bg2 d5 92.Kxh4 d4 93.Kg4 d3 94.Kf3 d2 95.Ke2 Be3 96.f5 Kd6 97.Bh3 Ke5 98.Kd1= White could keep the position playing his king on d1 and e2 squares.

76.Kxd2 Bh2

Diagram 4.

77.g4!

That is just the point!

77...Bxf4+

Note that after 77...hxg4 78.Ke3 (a pawns race after 78.h5 g3 79.h6 g2 80.h7 g1Q 81.h8Q Bxf4+ leads to the lose of the queen 82.Kd3 Qf1+ 83.Kc3 Qa1+-+ In case of 82.Ke2 Qe3+ 83.Kf1 Qc1+-+ White loses a piece.) 78.Ke3 Bg1+ 79.Ke2 Kb4 80.h5 gxh5 81.Bxf5 Kc4 82.Bg6 h4 83.Bf5 g3 84.Be6 Kd4 85.Kf3 Bf2 we see again the position annotated at the 75th move (diagram 3) where as we had said White could rich a draw after 86.Bh3! Kxd5 87.Kg4 Ke4 88.Bg2+ Kd4 89.Kxh4 d5 90.Kg4=

78.Ke2 hxg4 79.h5 gxh5 80.Bxf5 Kb4 81.Bg6 h4 82.Bf5 g3 83.Kf3 Kc4 84.Bh3 Be5

Diagram 5.

85.Ke4!

Preventing black king from getting to the d4-square. In this case White could not safe the game.

85...Bf6 86.Bf1+ Kc3 87.Bg2

The white king is protecting the d5-pawn. So the white bishop has a nice defensive position on g2.

87...Kc4 88.Bf1+ Kc5 89.Bg2 Be7 90.Bf1 Bd8 91.Bg2 Kc4 92.Bf1+ Kc3 93.Bg2 Kd2 94.Kf3!

If the black king tries to penetrate attacking the g2-bishop White will put his king on the h3-square with a draw.

94...Kd3 95.Kg4 Ke3 96.Kh3 Bf6 97.Bh1 1/2-1/2

Draw

Let's go back to the position after 74th White's move to see the way to draw for Black.

Diagram 6.

74...Kb5!

As has been said black king stands near the d5-pawn.

75.Bc2

White defends as in the game. In case of 75.Kxd2 the next line leads to the win: 75...Bf2 76.Be2+ Kc5-+ 77.Bd1 Kb4! (it is early to take the white pawns because after 77...Kxd5 78.Ke2 Bxg3 79.Kf3 Bxh4 80.Bb3+ Kd4 81.Bf7= or 77...Bxg3 78.Ke3 Bxh4 79.Ba4= white bishop recovers his liberty with draw.) 78.Be2 Bxg3 79.Ke3 Bxh4 80.Ba6 Kc5-+ And the position after the 77th White's move arises. (See the notes below.)

75...Bg1 76.Kxd2 Bh2 77.g4

An unsuccessful effort is use of white king's position on the light square 77.Bd3+. After 77...Kc5 78.Ke3 (in case of 78.Bc2 black answers 78...Kb4! 79.Bd3 Bxg3 80.Ke3 Ka5-+ and doesn't let white bishop to penetrate into his position.) 78...Bxg3 79.Ba6 Bxh4 (in case of 79...Kxd5 80.Bc8= only draw) 80.Bc8 and Black has a way to victory.

Diagram 7.

It is just time to start the struggle for black pawns' safety on the kingside. 80...Bf6! (if not after 80...Kxd5 81.Bd7 Be1 82.Be8 Ke6 83.Bxg6 h4 84.Bh7 h3 85.Bg8+ Kf6 86.Bd5=I it would be a draw) 81.Be6 h4 82.Bf7 g5.After 83.fxg5 (in case of 83.Be6 Bd4+ 84.Kf3 g4+ 85.Kg2 g3 86.Kf3 Bf6 87.Kg2 Kd4 88.Kf3 Be7 89.Bf7 Bf8 90.Be6 Bh6! White is in zugzwang and is forced to allow the third black passed pawn after 91.Bxf5 - there is no 91.Bf7 because of 91...Bxf4!-+ - 91...Kxd5 92.Bh3 Kd4 93.f5 Bg5 94.Kg4 Be7 95.Kf4 d5-+) 83...Bxg5+ 84.Kf3 Kd4 85.Be6 Ke5 86.Bg8 Bf4 87.Kg2 Bg3 88.Kf3 f4 89.Be6 Kd4 90.Kg2 (White is obligated to concede the e4-pawn because 90.Bf7 is not good: h3 91.Be6 h2 92.Kg2 f3+ 93.Kh1 f2 94.Bh3 Kxd5-+) 90...Ke4 91.Kf1 f3 92.Kg1 Ke3 93.Kf1 Be5 94.Bc8 Kf4 95.Kg1 (95.Kf2 loses because of 95...Bd4+ 96.Kf1 Kg3-+ with the idea of 97...h3) 95...Kg3 96.Be6 Bd4+ (in case of 96...h3? due to a stalemate after 97.Kh1 Kf2 98.Bxh3 Ke1 99.Bf1= a draw could happen) 97.Kh1 Kf2 98.Bd7 Ke1 99.Bb5 f2 100.Kg2 h3+-+ White can do nothing against the advance of black f and h-pawns.

Diagram 8.

77...hxg4!?

If the black king were on b5 this move would be a winning one. But the text way to play could lead to victory too. After 77...Bxf4+ 78.Ke2 hxg4 79.h5 gxh5 80.Bxf5 Kc4 81.Bg6 h4 82.Bf5 g3 83.Kf3 Be5 84.Be6 the position is similar to one from the text.

Diagram 9.

But here after 84...Kd4! (If 84...h3 then 85.Bxh3 Kxd5 86.Ke3 Kc4 87.Bf1+ Kc5 88.Bg2 d5 89.Kd3=) Black manages not to allow the white king to get the e4-square and therefore opponent's bishop can't go to g2. After 85.Kg2 Ke4 86.Kg1 the transference of the black bishop on f4 via (immediate 86...h3 is not good because of 87.Bxh3 Kxd5 88.Kf1 Kd4 89.Ke2 d5 90.Bg2 Bf4 91.Kf3 Bd6 92.Ke2 Kc4 93.Kd2 Bf4+ 94.Kc2 d4 95.Bf1+ Kd5 96.Bg2+ Ke5 97.Kd3= and Black can strengthen his position.) 86...Bg7 87.Kg2 Bf6 88.Bf7 Be5 89.Be6 (if 89.Kg1, then 89...h3-+) 89...Bf4! decides the game.

Diagram 10.

Zugzwang. White is forced to play 90.Kg1 (90.Kf1 loses because of 90...Kf3 91.Bh3 Be3 92.Bg2+ Kg4-+ or 90.Bf7 90...h3+ 91.Kxh3 Kf3-+) 90...h3! (now it is the time to get a pair of not connected passed pawns "d"and "g") 91.Bxh3 Kxd5 92.Bg2+ (the move 92.Kg2 Ke4 93.Bc8 can't salvage because of 93...d5 94.Bb7 Be5 95.Kf1 Kd4 96.Ke2 Kc4 97.Ba6+ Kc3-+) 92.Bg2+ Kd4 93.Kf1 d5 94.Ke2 Kc4 (white king doesn't have the d2-square because of the bishop situated on f4.) 95.Kf3 Bd6 96.Ke2 d4 97.Be4 Kc3 98.Bf5 Be7 (not 98...g2?? Because of 99.Kf2=) 99.Be4.

Diagram 11.

99...Bh4! - the final fineness. It is important to control the f2-square. After100.Bg2 d3+ 101.Kd1 Kd4 102.Kd2 Bg5+ 103.Kd1 Ke3 104.Ke1 d2+ 105.Kd1 Kf2-+ there is no stopping black pawns.

78.Ke3

78.h5 loses because of 78...g3 79.Bd3+ Kc5 80.Bf1 gxh5 81.Bg2 Kd4 82.Ke2 h4 83.Kd2 Bg1-+ and the transference of the bishop on e3 decides.

78...Kc4

Black king managed to reach the white d5-pawn.

79.h5 gxh5 80.Bxf5 Kxd5 81.Bg6 h4 82.Bf5 Bg1+ 83.Ke2 g3 84.Kf3 Bb6 85.Bh3 Kd4 86.Kg4 Bd8-+

Diagram 12.

Obviously Black cannot stop black pawns' trio.

Position of the day Black to move and win. New FIDE rating list 01.01.14 A.Khalifman. TOT ZIENS! 27.02.07 A.Khalifman. WILL IT GET BORING? 02.02.07	Opposite-coloured geometry lesson! A. Khalifman, O. Biriukov. A curious ending arose in the J.Polgar - V.Kramnik game of the 7th round in Wijk aan Zee. During on-line translation ICC was aboil with controversy. The question was: "Will Black win or it will be a draw?" But neither the participants of this game nor leading chess players have expressed their opinion on the point after the game.A curious ending arose in the J.Polgar - V.Kramnik game of the 7th round in Wijk aan Zee. During on-line translation ICC was aboil with controversy. The question was: "Will Black win or it will be a draw?" But neither the participants of this game nor leading chess players have expressed their opinion on the point after the game. Diagram 1. (After the 71th White's move.) 71...Rd2! A crucial position. Black's pieces are situated on the best squares. Now Black forces a bishop ending where his king will have a possibility to get white pawns via queenside. Note that White must keep his rook on d3. If not the d5-pawn would be lost. And there are no any other reasonable moves except rook's exchange. That's zugzwang. 72.Rxd2 exd2 The passed pawn changed the file (it is on the d-file now) and it came nearer to the queening square. Black with his next moves will be forced to protect the d1-square not only by the bishop but by the king also. 73.Bd1 Kb6 74.Ke2 Diagram 2. 74...Ka5? At this moment thre were not more than 10 min. on the V.Kramnik's clock. So he had made a mistake which helped White to save the game. Yes, Black's move is understandable if you are a human player. Black king goes to d2-pawn's aid via black squares avoiding unacceptable White's surprises. But there is no rule without an exception. In this case it was necessary to put the king just on the white square: 74.Kb5! The thing is that the king is 1 move nearer to the d5-pawn (in distinction from the text move). And the d5-pawn is a potential target for black pieces. We'll consider bellow what would happen after 74. Kb5! But now let's see how White managed to draw after a5. 75.Bc2! White is preparing a breakthrough g3-g4 on the kingside trying to do away with his weak pawns with a minimal loss. 75...Bg1 Black is going to put his bishop on h2 with the idea of destruction white pawns on the kingside. It seems White's previous move mistake cannot be corrected. After 75...Kb4 76.Kxd2 (White should not be at a stop because after 76.Bd1 Bg1 77.Bc2 Bh2 78.Kf2 Kc3 79.Ba4 Kb2-+ Black will win easily extending the defensive of White.) 76...Bf2 77.g4 hxg4 78.h5 gxh5 79.Bxf5 Kc5 80.Ke2 Bd4 (the same position arises after 80...Bg1 81.Bg6 h4 82.Bf5 g3 83.Be6 Kd4 84.Kf3=) 81.Be6 Bf6 82.Bf7 h4 83.Be6 g3 84.Kf3 Kd4 85.Bf7 Bd8 86.Be6 Ba5 87.Bf7 Be1 88.Be6 Bf2. And though White is in zugzwang he can keep the position due to his passed f-pawn. Diagram 3. Playing 89.Bh3! (White can't keep his bishop on the a2-g8 diagonal because after 89.Bf7 89...h3 90.Be6 h2 91.Kg2 Ke4 92.f5 h1Q+ 93.Kxh1 Kf3-+ Black wins. In case of 89.f5 after 89...Ke5 90.Kg2 Bb6 91.Kf3 Bd8 92.Kg2 Kf4-+ Now, if White wants to get back the control under the c8-h3 diagonal he must give the "f" pawn. But it is unacceptable to him. The same thing would happen after 89.Kg2 Ke4 90.f5 Ke5-+) 89...Kxd5 90.Kg4 Kc5 91.Bg2 d5 92.Kxh4 d4 93.Kg4 d3 94.Kf3 d2 95.Ke2 Be3 96.f5 Kd6 97.Bh3 Ke5 98.Kd1= White could keep the position playing his king on d1 and e2 squares. 76.Kxd2 Bh2 Diagram 4. 77.g4! That is just the point! 77...Bxf4+ Note that after 77...hxg4 78.Ke3 (a pawns race after 78.h5 g3 79.h6 g2 80.h7 g1Q 81.h8Q Bxf4+ leads to the lose of the queen 82.Kd3 Qf1+ 83.Kc3 Qa1+-+ In case of 82.Ke2 Qe3+ 83.Kf1 Qc1+-+ White loses a piece.) 78.Ke3 Bg1+ 79.Ke2 Kb4 80.h5 gxh5 81.Bxf5 Kc4 82.Bg6 h4 83.Bf5 g3 84.Be6 Kd4 85.Kf3 Bf2 we see again the position annotated at the 75th move (diagram 3) where as we had said White could rich a draw after 86.Bh3! Kxd5 87.Kg4 Ke4 88.Bg2+ Kd4 89.Kxh4 d5 90.Kg4= 78.Ke2 hxg4 79.h5 gxh5 80.Bxf5 Kb4 81.Bg6 h4 82.Bf5 g3 83.Kf3 Kc4 84.Bh3 Be5 Diagram 5. 85.Ke4! Preventing black king from getting to the d4-square. In this case White could not safe the game. 85...Bf6 86.Bf1+ Kc3 87.Bg2 The white king is protecting the d5-pawn. So the white bishop has a nice defensive position on g2. 87...Kc4 88.Bf1+ Kc5 89.Bg2 Be7 90.Bf1 Bd8 91.Bg2 Kc4 92.Bf1+ Kc3 93.Bg2 Kd2 94.Kf3! If the black king tries to penetrate attacking the g2-bishop White will put his king on the h3-square with a draw. 94...Kd3 95.Kg4 Ke3 96.Kh3 Bf6 97.Bh1 1/2-1/2 Draw Let's go back to the position after 74th White's move to see the way to draw for Black. Diagram 6. 74...Kb5! As has been said black king stands near the d5-pawn. 75.Bc2 White defends as in the game. In case of 75.Kxd2 the next line leads to the win: 75...Bf2 76.Be2+ Kc5-+ 77.Bd1 Kb4! (it is early to take the white pawns because after 77...Kxd5 78.Ke2 Bxg3 79.Kf3 Bxh4 80.Bb3+ Kd4 81.Bf7= or 77...Bxg3 78.Ke3 Bxh4 79.Ba4= white bishop recovers his liberty with draw.) 78.Be2 Bxg3 79.Ke3 Bxh4 80.Ba6 Kc5-+ And the position after the 77th White's move arises. (See the notes below.) 75...Bg1 76.Kxd2 Bh2 77.g4 An unsuccessful effort is use of white king's position on the light square 77.Bd3+. After 77...Kc5 78.Ke3 (in case of 78.Bc2 black answers 78...Kb4! 79.Bd3 Bxg3 80.Ke3 Ka5-+ and doesn't let white bishop to penetrate into his position.) 78...Bxg3 79.Ba6 Bxh4 (in case of 79...Kxd5 80.Bc8= only draw) 80.Bc8 and Black has a way to victory. Diagram 7. It is just time to start the struggle for black pawns' safety on the kingside. 80...Bf6! (if not after 80...Kxd5 81.Bd7 Be1 82.Be8 Ke6 83.Bxg6 h4 84.Bh7 h3 85.Bg8+ Kf6 86.Bd5=I it would be a draw) 81.Be6 h4 82.Bf7 g5.After 83.fxg5 (in case of 83.Be6 Bd4+ 84.Kf3 g4+ 85.Kg2 g3 86.Kf3 Bf6 87.Kg2 Kd4 88.Kf3 Be7 89.Bf7 Bf8 90.Be6 Bh6! White is in zugzwang and is forced to allow the third black passed pawn after 91.Bxf5 - there is no 91.Bf7 because of 91...Bxf4!-+ - 91...Kxd5 92.Bh3 Kd4 93.f5 Bg5 94.Kg4 Be7 95.Kf4 d5-+) 83...Bxg5+ 84.Kf3 Kd4 85.Be6 Ke5 86.Bg8 Bf4 87.Kg2 Bg3 88.Kf3 f4 89.Be6 Kd4 90.Kg2 (White is obligated to concede the e4-pawn because 90.Bf7 is not good: h3 91.Be6 h2 92.Kg2 f3+ 93.Kh1 f2 94.Bh3 Kxd5-+) 90...Ke4 91.Kf1 f3 92.Kg1 Ke3 93.Kf1 Be5 94.Bc8 Kf4 95.Kg1 (95.Kf2 loses because of 95...Bd4+ 96.Kf1 Kg3-+ with the idea of 97...h3) 95...Kg3 96.Be6 Bd4+ (in case of 96...h3? due to a stalemate after 97.Kh1 Kf2 98.Bxh3 Ke1 99.Bf1= a draw could happen) 97.Kh1 Kf2 98.Bd7 Ke1 99.Bb5 f2 100.Kg2 h3+-+ White can do nothing against the advance of black f and h-pawns. Diagram 8. 77...hxg4!? If the black king were on b5 this move would be a winning one. But the text way to play could lead to victory too. After 77...Bxf4+ 78.Ke2 hxg4 79.h5 gxh5 80.Bxf5 Kc4 81.Bg6 h4 82.Bf5 g3 83.Kf3 Be5 84.Be6 the position is similar to one from the text. Diagram 9. But here after 84...Kd4! (If 84...h3 then 85.Bxh3 Kxd5 86.Ke3 Kc4 87.Bf1+ Kc5 88.Bg2 d5 89.Kd3=) Black manages not to allow the white king to get the e4-square and therefore opponent's bishop can't go to g2. After 85.Kg2 Ke4 86.Kg1 the transference of the black bishop on f4 via (immediate 86...h3 is not good because of 87.Bxh3 Kxd5 88.Kf1 Kd4 89.Ke2 d5 90.Bg2 Bf4 91.Kf3 Bd6 92.Ke2 Kc4 93.Kd2 Bf4+ 94.Kc2 d4 95.Bf1+ Kd5 96.Bg2+ Ke5 97.Kd3= and Black can strengthen his position.) 86...Bg7 87.Kg2 Bf6 88.Bf7 Be5 89.Be6 (if 89.Kg1, then 89...h3-+) 89...Bf4! decides the game. Diagram 10. Zugzwang. White is forced to play 90.Kg1 (90.Kf1 loses because of 90...Kf3 91.Bh3 Be3 92.Bg2+ Kg4-+ or 90.Bf7 90...h3+ 91.Kxh3 Kf3-+) 90...h3! (now it is the time to get a pair of not connected passed pawns "d"and "g") 91.Bxh3 Kxd5 92.Bg2+ (the move 92.Kg2 Ke4 93.Bc8 can't salvage because of 93...d5 94.Bb7 Be5 95.Kf1 Kd4 96.Ke2 Kc4 97.Ba6+ Kc3-+) 92.Bg2+ Kd4 93.Kf1 d5 94.Ke2 Kc4 (white king doesn't have the d2-square because of the bishop situated on f4.) 95.Kf3 Bd6 96.Ke2 d4 97.Be4 Kc3 98.Bf5 Be7 (not 98...g2?? Because of 99.Kf2=) 99.Be4. Diagram 11. 99...Bh4! - the final fineness. It is important to control the f2-square. After100.Bg2 d3+ 101.Kd1 Kd4 102.Kd2 Bg5+ 103.Kd1 Ke3 104.Ke1 d2+ 105.Kd1 Kf2-+ there is no stopping black pawns. 78.Ke3 78.h5 loses because of 78...g3 79.Bd3+ Kc5 80.Bf1 gxh5 81.Bg2 Kd4 82.Ke2 h4 83.Kd2 Bg1-+ and the transference of the bishop on e3 decides. 78...Kc4 Black king managed to reach the white d5-pawn. 79.h5 gxh5 80.Bxf5 Kxd5 81.Bg6 h4 82.Bf5 Bg1+ 83.Ke2 g3 84.Kf3 Bb6 85.Bh3 Kd4 86.Kg4 Bd8-+ Diagram 12. Obviously Black cannot stop black pawns' trio. More articles A.Khalifman. TOT ZIENS! 27.02.07 A.Khalifman. WILL IT GET BORING? 02.02.07 A.Khalifman. Everything is going according to plan. Almost everything. 02.02.07 Lonely Knight Dance. To the light memory of G.M.Chepukaitis is dedicated. 13.10.2005 In one game... 10.12.2004 In the beginning of June our school was visited group of schoolchildren from USA. 30.06.2004 A.Khalifman. A Midsummer Night's Dream., 02.07.2004 A. Khalifman, O. Biriukov. Opposite-coloured geometry lesson, 17.02.2003 Happy New Year!, 16.01.2003 Autumn came round. Mastodons are going to come soon..., 09.09.2002 Queen's Gambit (by Kenneth Curmi), 24.08.2002 Chess Summer, 19.08.2002 Amazing and usual Dortmund, 06.08.2002	HOME LINKS ARTICLES GUESTBOOK NALIMOV EGTB FIDE RATINGS ABOUT SCHOOL ABOUT PRICES & CONDITIONS SAMPLE LECTURE OUR TEACHERS CHESS STARS PUBLISHING

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Opposite-coloured geometry lesson!

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