Queen versus pawn endgame

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This article uses algebraic notation to describe chess moves.

The chess endgame of a queen versus pawn (with both sides having no other pieces other than the king) is usually an easy win for the side with the queen. However, if the pawn has advanced to its seventh rank it has possibilities of reaching a draw, and there are some drawn positions with the pawn on the sixth rank. This endgame arises most often from a race of pawns to promote.

We will call the side with the queen the attacker and the side with the pawn the defender. Assume that the attacker has the move.

If the pawn is not beyond its sixth rank, the attacker (to move) usually wins easily, but there are a few exceptions. The winning process is to either get the queen on a square in front of the pawn and getting the king over to help win the pawn or to check the defending king until it is forced in front of the pawn and using that tempo to bring the king closer, until it can assist in winning the pawn (Fine & Benko 2003:529). After the pawn is won, the attacker has an elementary checkmate (Seirawan 2003:49-53).

1 Queen versus a pawn on the sixth rank
2 Queen versus a pawn on the seventh rank
3 References
4 External links

[edit] Queen versus a pawn on the sixth rank

Black to move, White wins.

The queen usually wins easily if the pawn is on the sixth rank. In the first position, Black is to move, but White wins.

1... Kg2
2. Qg4+ Kf2
3. Kb7 Ke3
4. Kc6 f2
5. Qd1 Kf4
6. Qf1 and White wins (Fine & Benko 2003:530).

White to move, draw (a rare exception).

Exceptions can occur when the king blocks the queen on a file or diagonal, as in the second position.

1. Qh1+ Kb2!

White needs to pin the pawn by 2. Qh8, but the king blocks the pin.

2. Qb7+

This was White's only check which prevents the pawn from advancing, and Black responds

2... Kc1!

repeating the position. If the white king is anywhere else, the queen can pin the pawn and allow for the queen and then the king to approach (Fine & Benko 2003:530).

[edit] Queen versus a pawn on the seventh rank

White wins by 1. Qg5!, followed by 2. Qc1

In order for the defending side to have a chance at a draw (with the other side to move), the pawn must be on its seventh rank and the king must be near by (plus a few drawing positions with the pawn on the sixth rank, as above). Except for unusual cases, the attacking side wins if the pawn is a knight pawn (b- or g-files) or a central pawn (d- or e-files). For bishop pawns and rook pawns, the result depends on the location of the kings. If the attacking king is close enough to the pawn, it wins; otherwise a draw results (Seirawan 2003:49-53).

First note that the attacker may win easily, depending on the location of the kings. In this position, White wins by 1. Qg5! followed by 2. Qc1, and then the white king is brought nearer to win the pawn. If the black king is on any other square around the pawn, the position is a draw (position modified slightly) (Flear 2004:155).

[edit] Central pawn or knight pawn

Black to move, White wins. White also wins against a knight pawn.

If the pawn is a central pawn or knight pawn (i.e. on the b, d, e, or g file), the queen wins easily, except for a few exceptional positions. In the position on the right, White wins. It takes several moves, but it is not difficult.

1... Ke3

Black threatens to queen the pawn. White prevents this by forcing the black king in front of the pawn.

2. Qh4 Kd2
3. Qd4+ Kc2
4. Qe3 Kd1
5. Qd3+ Ke1

Without the immediate threat of promotion, White has gained a tempo that can be used to bring his king closer. This process is repeated.

6. Kc6 Kf2
7. Qd2 Kf1
8. Qf4+ Kg1
9. Qe3+ Kf1
10. Qf3+ Ke1

And now White can again bring his king closer.

11. Kd5 Kd2
12. Qf2 Kd1
13. Qd4+ Kc2
14. Qe3 Kd1
15. Qd3+ Ke1
16. Ke4! Kf2
17. Qf3+ Ke1
18. Kd3

and White wins the pawn and then checkmates. The winning process with a knight pawn is the same (Seirawan 2003:49-53).

White to move. Draw if the white king is on any of the marked squares, otherwise White wins.

In some cases, the attacking king can block its own queen, as in the second diagram. If the white king is on any of the marked squares, the queen cannot approach the pawn, and the result is a draw (Müller & Lamprecht 2001:40-41).

[edit] Rook pawn

White to move, draw.

The process above doesn't work against a rook pawn. The reason is that when the king was forced in front of his pawn, he could move out the other side on the next move. With a rook pawn, this file isn't available, and there can be a stalemate.

In the first position, if the procedure above is tried,

1. Qd4+ Kb1
2. Qb4+ Kc2
3. Qa3 Kb1
4. Qb3+ Ka1!

and now the position is a stalemate unless White lets the black king back to the b-file. White can make no progress (Seirawan 2003:49-53).

White to move, White wins if his king is inside the region marked with "X"s.

White can win similar positions if his king is close enough to the pawn. In the second position, white's king is close enough to win – by allowing the pawn to promote but then checkmating the king (Seirawan 2003:49-53).

1. Qf6+ Kb1 (if 1... Kc2 then 2. Qa1 wins)
2. Qf1+ Kb2
3. Qe2+ Kb1 (3... Kb3 allows 4. Qe5 followed by 5. Qa1)
4. Kc4! a1=Q
5. Kb3

and White checkmates.

If the white king was on e3, the win is simple:

1. Qd2+ Kb1
2. Kd3 a1=Q
3. Qc2#

[edit] Bishop pawn

White to move, draw.

A bishop pawn may also draw, but for a different reason (a different stalemate position).

1. Qb6+ Ka1!
2. Qd4+ Kb1
3. Qb4+ Ka1
4. Qc3+ Kb1
5. Qb3+ Ka1!

and White can not capture the pawn because stalemate would result (Seirawan 2003:49-53). The rule is that White wins if his king is close enough to reach b3 within two moves or d2 in one move, because it can assist in checkmate (Müller & Lamprecht 2003:41).

If the defending king is not on the side of the pawn near the corner and the attacking king is close enough, the game can still be won – often by letting the pawn promote and then checkmating.

White to move, White wins.

In the second position in this section, the king must be prevented from getting to the other side of his pawn, otherwise he can employ the stalemate defense.

1. Qb3! Kd2
2. Qb2 Kd1
3. Kf3! Kd2 (3... c1=Q 4.Qe2#, or 3... c1=N and White checkmates in three moves: 4. Ke3 Nb3 5. Qc3, and checkmate on the next move.)
4. Kf2 Kd1
5. Qd4+ Kc1
6. Qb4! Kd1
7. Qe1# (Fine & Benko 2003:526-29).

White to move, White wins.

The third position shows another win for the attacker, since his king is close and the defending king is not (yet) near the corner.

1. Qc4+ Ke1
2. Qe4+ Kf1
3. Kf4 Kg1 (the black king gets to the corner, but White has moved his king close enough to checkmate.)
4. Qd4 Kh1
5. Kg3 (of course not 5. Qxf2 stalemate)
5... f1=Q
6. Qh8+

and White checkmates in two more moves (Snape 2003:88). Note that it is possible to win against a bishop pawn on the seventh rank and the king in the corner if the attacking king and queen are in the proper position.