Saturday, May 14, 2011

Rook Endings at SEA Selection - Part 2

Let us examine a few more basic positions. 

Philidor position - Black to move draw
 On the left is the Philidor position. This is a standard drawing position where the pawn and attacking king has not advanced beyond the 5th rank. Black's King holds the Queening square, and the Black Rook holds the sixth rank.

Black merely plays his rook back and forth on his own 3rd rank. To improve his position, white has to advance his pawn , whereupon black will transfer his rook down the board to give checks. 1...Rc6 2. e6 Rc1! 3. Kg6 Rg1+ 4.Kf5 Rf1+ etc etc.

In the position, moving away from the 3rd rank will be dangerous but not losing yet. However you need to be aware of the winning possibilities e.g 1...Rb1 2. Kf6 Rf1+ 3. Ke6 Re1 4. Ra8+ Kg7 5. Kd6 Kf7! (black prevents the pawn from advancing) 6. Ra7+  Ke8 7. Ke6 Kf8 reaches the same position. A further try to win is 8. Ra8+ Kg7 9. Re8 (White supports the pawn and prepares to move his king out of the way) Ra1! and we will reach positions similar to the next diagram eventually.

Black to move and draw
The attacking side can win if the pawn reaches the seventh rank successfully. But even here there is a possible draw if the defender can position his pieces correctly. In the diagram on the left we can see there is a short side (red arrow) and a long side ( indicated by the blue arrow). If the defending king can get to the short side and his rook occupy the long side he can draw provided there is three files separating his rook from the king. In the diagram with black rook is only two files away from the king and now he loses. 1...Rb8+ 2.Kd7 Rb7+ 3. Kd6 Rb8 4. Kc7 (We can see why three files are needed. If the rook was already on the a-file then this would not work because black can continue checking 4...Ra7+ , now this is not possible) 4...Ra8 5. Ra3! (Only this moves win 5.Re1? Kf7 6.Kd7 Ra7+ and the white king can escape checks but will lose the pawn) 7.Kd6 Ra6+ 8. Kc5 Ra5+ 9. Kb6 Ra8 etc.

Lucena position, black loses

The Lucena position has the defending king on one side of the pawn and the rook on the other. If white's king tries to vacate the queening square, he cannot escape rook checks. E.g 1. Kd7 Rd1+ 2. Ke6 Re1+ 3. Kf6 Rf1+ and so on. The winning maneuver is called bridge building. 1. Rc4 Rf2 2.Kd7 Rd2+ 3. Ke6 Re2+ 4. Kd6 Rd2+ 5.Ke5 Re2+ 6.Re5 and the pawn queens.

1st rank defence
 The above diagram shows a situation where the pawn has advanced too fast and the attacking side failed to control the queening square. White draws by moving his rook along the first rank. 1. Re1 Rb2 2. Ra1 Rc2 3. Re1 etc.

Now we can get to the actual game armed with all these knowledge.

Fong Yit Ho-IM Mok, Round 8
Black has a very active position. Compare the two rooks , black rook is attacking the h-pawn and white rook is passively defending it from behind. Passive defence usually loses in rook endings. In order to have any chance of drawing, white must transfer his rook to the other side and start attacking enemy pawns.  56....e4 57. fxe4 fxe4 58. Ke3 Ke5 59. f3 f5 60. fxe4 fxe4 61. a4  Yit Ho understands that he must open the queen-side and try to exchange as many pawns as possible

Rf4 62. axb5 axb5 63. Rc1 Its now or never, passive defence loses quickly. Rf3+ 64. Ke2 Rxh3 65. Rc5+ Kd4   66. Rxb5 Rh2+ 67. Kf1 Ke3 This seems the most obvious but is not the best way to win. Simplest is 65...h4 66. Rh5 e3 67. b5 Rf2+  68.Ke1 (68.Kg1 Rf4 followed by ...e3)  Rb2 69. Rxh4+ Kd3 and the mate threat wins e.g 70. Kf1 Rb1+ 71. Kg2 e2 . 68. Rd5 68..Rb8 h4 69. Kg1 Rb2 70. b5 Rxb6 71. b6 Rb2 72. Rb7  h3 73. Kh1 and surprisingly black cannot win as the white pawn on b6 prevents any bridge building maneuver e.g 73...Ke2 74. Kh2 e3 75. Kxh3 Kf2 76. Rf7+  Ke1 77. b7 e2 and neither side can progress. 69...h4 70. b5 Rb2 ( h3 71. Kg2 Rb2 72. Rd8 Rxb3 73. Rb8 reaches a similar drawn position)

70. Rh5?? (This exchanges into one of the basic lost positions. As shown just now, white can draw by defending his last b-pawn. 70. Rd8 h3 71. Kg1 Rxb3 72. Rb8) Rxb3 71. Rxh4 Rb1+ 72. Kg2 Rxb5 

Can white draw this position? Few points -
a) black pawn is still on 5th rank
b) white king is in the correct side (short side)
c) white rook is badly placed and need to re-locate to the long side

As it turns out, white cannot prevent black reaching Lucena position e.g 73. Ra1 Ke2 74. Ra8 Rg5+ 75.Kh3 d6 76. Re1 Kf2 77. Rf8+ Ke1 78. Kh4 Rg7 79. Kh3 e2 80 Re1 Rg5 etc

73. Kf1 Rb1+ 74. Kg2 Kd3 75. Rh8 Ke2?? Black can take advantage of the white rook placing by advancing immediately, 75...e3 76. Rd8+ (otherwise 77...e2 it is over) Ke2 77. Ra8 Ke1 78. Rh8 Rb2+ 79. Kf3 e2 and there is no stopping the pawn.

76. Ra8! Rb2 77. Ra1 Rc2 78. Rb1? White should not give up the a-file. 78.Kg3 draws

Ra2 79. Rc1?? Kd2 80. Rb1 Ke2 80...Ke3+ 81. Kg3 Ke2 82. Kg2 e3 (see diagram below)

 83. Kg3 Ra8 84. Rb2+ Kd1 85 Rb1+Kc2 86. Rb7 Re7 and queens. If white goes to 81.Kg1 then Kf3 82. Rb8 e3 83. Rf1+ Ke2 84. Rd8 Ke1 85. Rd7 e2 and reaches the Lucena position.

81. Rc1 e3 82. Rb1 Rd2?? What happens if black tries 82...Ra8 83. Rb2+ Kd1 84. Rb1+ Kc2 85. Rb7 Re7 the problem is the white king is on g2 and not g3 as in the previous note and he can play 86. Kf1 Kd2 87. Rd7+ and draws. But actually black can win with 82...Kd3+

a) 83. Kf1 Kd2 84.Kg2 Ke2 (white is in zugzwang and must give up the back rank) 85. Rb8 Ra1 86. Rb7 Kd2 87. Rd7+ Ke1 88. Kf3 e2 89. Kg2 Ra8 reaches Lucena again.
b)83. Kf3 Kd2 84.  Kg2 Ke2 reaches the diagram above.

83. Ra1 Rb2 84.Rc1 Kd3+ 85. Kf1 Rf2+  85...Kd2 86. Ra1e2+ 87. Kf2 draws

86. Ke1 Rh2 87. Rd1+ Ke4 88. Rd8 1/2-1/2

As you can see, a "simple" looking rook ending is not really that simple especially with a clock ticking away at your side.


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