Notes by David Joyner. (No claim to completeness - see class handouts.)
We shall study in this lesson a new method for solving king and pawn endgame problems where the pawn structure is static (fixed). The method of coordinating squares, touched upon in lesson 2, uses three steps for solving such problems:
Position 3.1: Study by the Hungarian problem composer Ebers (Maguar Sakkvilag, 1930).
In Forsyth notation:
8/1p5k/1P1p4/3p4/3Pp2p/2K1P2p/7P/8
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1. Kb2 Kg8 2. Ka1 Kf8 3. Ka2 Ke7 4. Kb3 Kd7 5. Kb4 Kc6 6. Ka5! (this will turn out to define a "critical position") Kd7 7. Kb4 Ke6 8. Kc3 Kf5 9. d2 g4 10. e2 Kf5 draw. Note that the position after 6. Ka5! is lost for white if it were white to move. (Since it is impossible for white to penetrate blacks position, it is practically impossible for black to lose, so by definition it is not a mutual zuzswang.) If white tried to blockade the black king from the c6 square by playing Kb5 at some point he would lose! (With the white king on b5, the black king on d7, the pawns as above, and with black to move, the white king cannot get back to block the black king from f3 fast enough.) This is a critical position and defines a5-c6 as coordinating squares. Going back one move, we see that b4-d7 are also coordinating squares. (Actually, it is a priori possible that a4-d7 are coordinating squares but with the white king on b4, the black king on d7, the pawns as above, and with black to move, the white king cannot get back to block the black king from f3 fast enough, so white loses. Thus a4-d7 can be ruled out.)
Another solution: 1. Kb2 Kh6 2. Kc2 Kh5 3. Kd2 Kg6 4. Kc1 Kf6 5. Kc2 Kf7 6. Kb2 Ke6 7. Kc3 Kd7 8. Kb4 Kc6 9. Ka5! Kd7 10. Kb4 draw.
This study was mysterious and stunning to me when I first saw it. It is a very complex study to analyze. This study can be solved easily once you know my method of coordinating squares. The key idea is that black must try to exploit the two white weaknesses: the hole at f3 and the hole at c6.
Rule of 3 Adjacent Squares: The knowledge of the coordinating squares of any three adjacent squares (at most one of which is allowed to be a square of exception) neighboring a given square determines the coordinating square of that square.
Summarizing what we know so far,
a5 <-----> c6
/ \
a4 - b4 <-----> d7 - d8
\ /
b5 <-----> c7 (exceptional)
In addition, a2-h8, b2-h7, c2-h6, d2-h5 are coordinating squares.
This data gives rise the the solutions given above.
Position 3.1a: Study by Ebers (Maguar Sakkvilag, 1935).
In Forsyth notation:
4k3/5p1p/7P/6P1/p7/P7/8/1K6
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In Forsyth notation:
4k3/8/8/1p5p/1P5P/8/3K4/8
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In Forsyth notation:
8/5k2/2p5/1pPp4/p2P2p1/P2P2P1/P5K1/8
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() White to play and win |
In Forsyth notation:
4k3/5p1p/1p5P/6P1/P7/8/8/4K3
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The "critical positions" are (with black to move and pawns as in the diagrammed position):
The most easily determined "critical positions" are (with black to move and pawns as in the diagrammed position):
We claim: white king on d2, black king on f5, is a critical position. The only other possibility if the white king was on d2, would be if the black king on f6 was a draw for black (with black to move). Proof: 1. ... Ke6 2. Kc2! Kd7 (2 ... Ke7 3 Kc3 would transpose into the losing line above) 3. Kc3. Now if 3 ... Kd8 or 3 ... Kc7 or 3 ... Kc8 then 4. Kd2 and 5. Ke3 wins. If 3 ... Ke6,-7,-8 then 4. Kb4 and 5. Ka5 wins.
Therefore we have the following coordinating squares
Solution: 1. Kf2. Now either 1. ... Kf6 or 1. ... Ke6 is forced. If 1 ... Kf6 then 2. Ke2 Ke6 3. Kd2 Kd7 (3 ... Kf6 4. Kc3 wins the race to a6) 4. Ke3 wins the race to f4. If 1 ... Ke6 then 2. Ke2 Kf6 3. Kd2 and white wins as above. For example, 1. Kf2 Ke6 2 Ke2 Kf6 3 Kd2 Ke6 4 Kc2 Kd7 3 Kc3 Kc7 4 Kd2 Kd7 5 Ke3 Ke6 6 Kf4 and white wins.
First, the solution (given in class; R. Fine's Basic Chess Endings was referenced): 1 Kd2 (1 Ke2 Kd7 draws while 1 Kf2? loses!) Kd8 2 Ke2 Ke8 3 Kf3 Ke7 4 Ke3 Ke8 5 Kd4 Kd8 6 Ke4 Kd7 7 Kd5 Ke7 8 Kc6 and white wins.
The most easily determined "critical positions" are (with black to move and pawns as in the diagrammed position):