Wrong bishop (original) (raw)

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Situation in chess endgame

a b c d e f g h
8 b8 black kinga6 white kinga5 white pawnc5 white bishop 8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h

A wrong bishop in the situation of king, bishop, and rook pawn versus king

In a chess endgame, a wrong bishop is a bishop that would have been better placed on the opposite square color.[1] This most commonly occurs with a bishop and one of its rook pawns, but it also occurs with a rook versus a bishop, a rook and one rook pawn versus a bishop, and possibly with a rook and one bishop pawn versus a bishop.

V. Platov, 1925

a b c d e f g h
8 h8 black kinga7 white rooke5 white kingh4 black bishop 8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h

White wins because Black has the wrong bishop.

White wins in this position. The defender has the wrong bishop if it is on the same color as the corner where his king is confined. Black's bishop is on the wrong color of square for it to form a fortress in the corner (i.e. with the black king on the h8-square and the bishop on the g8- or h7-square). White wins:

1. Kf5! Kg8

2. Ra4!! The only way to win. If 2.Kg6? Kf8 and the black king is able to get out of the "dangerous corner" or "wrong corner" and head to a "safe corner" or "right corner" where he can set up the fortress.

2... Be1

3. Kg6 Kf8

4. Rf4+!, followed by 5. Re4, winning.[2]

There are some situations involving a rook pawn and the wrong bishop.

Bishop and rook pawn

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Müller & Lamprecht

a b c d e f g h
8 a8 black kinge7 white bishopa6 white pawnb6 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 has the wrong bishop, draw with either side to move

In an endgame with a bishop and a rook pawn, the wrong bishop is one that does not control the promotion square of the pawn. This position is a draw with either side to move. Black simply keeps his king on the a8-, a7-, or b8-squares (or b7 if the pawn advances) to keep the pawn from promoting. A draw because of stalemate is also possible. If the bishop were on the other color it could force the black king out of the corner and the pawn could promote and win.[3]

Rook and rook pawn versus bishop

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Bernhard von Guretzky-Cornitz

a b c d e f g h
8 h6 black kingh5 white pawnh4 white kingh3 white rookd2 black bishop 8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h

White wins, the bishop is on the wrong color.

A rook and a rook pawn always win against the wrong bishop, as in this position. The defender has the wrong bishop if it is the one on the same color as the pawn's promotion square. The winning procedure is to give up the pawn at the right time to get to a winning rook versus bishop endgame. If the bishop was on the other color, the defender may be able to form a fortress in the corner, as mentioned above.[4]

Rook and bishop pawn versus bishop

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de la Villa, diagram 13.19

a b c d e f g h
8 f8 black kingb7 white rookf6 white pawne5 white kingc4 black bishop 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 draws.

With a rook and a bishop pawn on the sixth rank versus a bishop, the bishop may be on the right color or the wrong color. In one case the rook and pawn win; in the other the bishop is able to draw. In this position Black is able to draw because his bishop is on the right color:

1... Be2

2. Kf4 Bc4

3. Kg5 Bd5!

4. Rc7 Ba2!

5. Kg6 Bb1+!

6. Kh6 Ba2!

7. Ra7 Bc4

and there is no way for White to make progress.[5] This type of position was studied by Ercole del Rio around 1750.[6][7] This case is similar to the case with a rook pawn (above), which also may be a draw.

Examples from games

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Szabó vs. Botvinnik, 1952

abcdefgh8c8 black bishopf8 black kingh7 black pawnf6 white pawna5 white pawne5 white knightg5 white rookg4 white pawna3 black rookd2 white king877665544332211abcdefghPosition before 51...Rxa5! abcdefgh8f8 black kinga7 white rookf6 white pawng5 white kingc4 black bishop877665544332211abcdefghPosition after 59...Bc4

In this 1952 game between László Szabó and World Champion Mikhail Botvinnik,[8] Black was defending two pawns down – a position that would normally be a win for White. Botvinnik saw an opportunity to exchange his rook for a knight and two pawns and reach a drawn position (even without his pawn). The game continued:

51... Rxa5!

52. Nd7+ Bxd7

53. Rxa5 Bxg4

54. Ke3 Be6

55. Kf4 Bc4

56. Ra7 h5

57. Kg5 h4

58. Kxh4 Bb3

59. Kg5 Bc4

and reached the second position, which had been analyzed as a draw.

White was not able to make any progress. He promoted his pawn on move 76 and it was immediately captured by Black, resulting in a rook versus bishop endgame (see pawnless chess endings#Common pawnless endings (rook and minor pieces)) that was drawn two moves later.[9]

Miladinovic vs. Beliavsky, 2001

abcdefgh8d6 white bishopf5 black kingg4 black pawnb3 black rookf3 white pawng3 white king877665544332211abcdefghBlack to move abcdefgh8c5 white bishopg3 black kinge2 white kingf2 black pawnh2 black rook877665544332211abcdefghPosition after 127.Bc5, draw

In this game[10] between Igor Miladinović and Alexander Beliavsky, Black could have won by 99... Rxf3+, but instead played 99... gxf3?, reaching the theoretically-drawn position.

99... gxf3?

100. Bc5 Ke4

101. Kf2 Rc3

102. Ba7 Rc7

103. Bb6 Rc2+

104. Kf1 Rc6 (if 104...f2 then 105.Kg2! draws)

105. Ba7 Ra6

106. Bc5 Kf4

107. Bd4 Ra4

108. Bc5 Rc4

109. Ba7 Rb4

110. Bc5

The game was drawn on move 127.[11]

Rook and pawn versus bishop and pawn

[edit]

From Hawkins, p. 104

abcdefgh8c6 black kinge6 black rookd5 black pawnd4 white pawnd3 white kingf3 white bishop877665544332211abcdefghDraw abcdefgh8c6 black kinge6 black rookd5 black pawne5 white bishopd4 white pawnd3 white king877665544332211abcdefghBlack wins

In this type of position when the pawns are facing each other and blocked, the result often depends on which color the bishop is on. If the bishop is on the same color as its pawn, the rook almost always wins. If the bishop is on the color of the opposing pawn it has good drawing chances.[12]

  1. ^ (Rosen 2003:61)
  2. ^ (Dvoretsky 2006:235, 366)
  3. ^ (Müller & Lamprecht 2001:96–100)
  4. ^ (Fine & Benko 2003:468–69)
  5. ^ (de la Villa 2008:219–21)
  6. ^ (Benko 2007:47–48)
  7. ^ (Giddins 2007:77)
  8. ^ Szabo vs. Botvinnik, 1952
  9. ^ (Giddins 2007:77)
  10. ^ Miladinovic vs. Beliavsky
  11. ^ (Makarov 2007:106–7)
  12. ^ (Hawkins 2012:90–93, 104)

Bibliography