Réti endgame study

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Chess kll45.svg Chess pll45.svg Chess kdl45.svg Chess pdl45.svg
Richard Réti

The Réti endgame study is a chess endgame study by Richard Réti. It was published in 1921 in Kagans Neueste Schachnachrichten. It demonstrates how a king can make multiple threats and how it can take more than one path to a given location, using the same number of moves. It is arguably the most famous endgame study and is covered in many books on the endgame (see chess endgame literature). The procedure is known as the "Réti Maneuver" or "Réti's Idea" (Müller & Pajeken 2008:32–33), (Nunn 2007:118–19), (Dvoretsky 2006:26). Endgame composer Abram Gurvich called the theme "The Hunt of Two Hares" and it appears in many other studies and games (Müller & Lamprecht 2007:39). It is also called "chasing two birds at once" (Dvoretsky 2006:26).


The study[edit]

Richard Réti, 1921
a b c d e f g h
8
Chessboard480.svg
h8 white king
a6 black king
c6 white pawn
h5 black pawn
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
White to play and draw

White is to move and draw in this position. At first inspection, it appears that White has no hope in drawing. His king is well outside the "square" of the black pawn (see king and pawn versus king endgame) and the king is a long way from supporting his own pawn. However, White can draw by making king moves that have two purposes. One goal is getting in the square of the black pawn, so it can be intercepted and the other is getting to the d6 square to support the promotion of his pawn.

The black king will have to spend two tempi to stop the white pawn from promoting, and this is the number of tempi the white king needs to gain in order to get into the square of the black pawn.

de la Villa, page 179
a b c d e f g h
8
Chessboard480.svg
e8 four
f8 two
g8 one
h8 white king
e7 five
f7 two
g7 one
h7 one
c6 white pawn
d6 nine
e6 three
f6 one
g6 two
h6 two
e5 one
f5 three
g5 five
h5 four
f4 black circle
g3 black circle
h2 black circle
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
Number of ways for the white king to get to squares in the minimum number of moves

The second diagram shows the number of ways that the white king can get to various squares in the minimum number of moves. There are nine ways to get to d6, but only one of them allows him to get into the square of the black pawn.

The solution is for the white king to follow the path on the diagonal marked by "1" and then follow the dots to intercept the black pawn (if necessary):

1. Kg7! h4
2. Kf6 Kb6 Black has to spend a tempo on preventing the white king from reaching his pawn. If 2... h3 then 3. Ke7 h2 4. c7 Kb7 5. Kd7 and both pawns promote, with a drawn position.
3. Ke5! Kxc6 Black has to spend another tempo to capture the pawn, to prevent the white king from protecting it. If 3... h3 then 4. Kd6 h2 5. c7 h1=Q 6. c8=Q, draw (Müller & Pajaken 2008:12–13). Now the white king has gained enough tempi to get in the square of the black pawn and intercept it:
4. Kf4, draw since the white king can stop the pawn from promoting (e.g. 4... h3 5. Kg3 h2 6. Kxh2) (de la Villa 2008:179–80).

Another study with the same idea[edit]

Richard Réti, 1928
a b c d e f g h
8
Chessboard480.svg
g7 black pawn
a6 black king
c6 white pawn
f6 black pawn
h6 black pawn
h5 white king
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
White to move and draw

Réti used the same idea in another study. The solution is:

1. Kg6 Kb6
2. Kxg7 f5
3. Kf6! f4
4. Ke5 f3
5. Kd6 f2
6. c7 f1Q
7. c8Q Qf4+
8. Kd5 ½-½ (Fishbein 1993:18–19)

Examples from games[edit]

Yates versus Marshall[edit]

Yates vs. Marshall, 1929
a b c d e f g h
8
Chessboard480.svg
a4 black pawn
b4 white king
f2 white pawn
b1 black king
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
Black to move

In this game[1] between Frederick Yates and Frank Marshall, Black draws using the same idea:

60... Kb2! (if 60... Kc2? 61. f4 wins)
61. Kxa4 (if 61. f4?? then 61... a3 wins)
61... Kc3!
62. f4 Kd4 ½-½ (Fishbein 1993:18–19), (Dvoretsky 2006:26–27)

Lasker versus Tarrasch[edit]

Lasker vs. Tarrasch, 1914
a b c d e f g h
8
Chessboard480.svg
g7 white king
a5 black pawn
b5 black pawn
c5 black pawn
f5 black king
b3 white pawn
b2 white pawn
h2 white pawn
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
White to move

In this 1914 game[2] between World Champion Emanuel Lasker and Siegbert Tarrasch, Black exchanged down into this position because he thought it was a win, but White used the maneuver above to draw the game.

40. h4 Kg4
41. Kg6! Threatening 42. h5 (Giddins 2007:8). Black had only considered the line: 41. Kf6? c4 42. bxc4 bxc4 43. Ke5 c3 44. bxc3 a4 45. Kd4 a3, winning (Kasparov 2003:209).
41... Kxh4 This move is forced and the white king gains a tempo to return on a different diagonal which is not obstructed by his pawns (Giddins 2007:8).
42. Kf5 Kg3
43. Ke4 Kf2
44. Kd5 Ke3
45. Kxc5 Kd3
46. Kxb5 Kc2
47. Kxa5 Kxb3 ½-½

The theme of this endgame was used later by Réti in the study (Kasparov 2003:210).

Notes[edit]

References[edit]

Further reading[edit]