Pawn endgame tactics Chess Puzzles

Background reading

King and pawn versus king endgame

The chess endgame with a king and a pawn versus a king is one of the most important and fundamental endgames, other than the basic checkmates. It is an important endgame for chess players to master, since most other endgames have the potential of reducing to this type of endgame via exchanges of pieces. Players need to be able to determine quickly whether a given position is a win or a draw, and to know the technique for playing it. The crux of this endgame is whether or not the pawn can be promoted (or queened), so checkmate can be forced. In the first paragraph of one of his books on endgames, Peter Griffiths emphasized the importance of this endgame: There is simply no substitute to a clear understanding of when and how these positions are won or drawn, not only so that one can play them accurately, but in order to recognize in advance what the correct result should be. If you can do that, you can exchange off quite confidently from a more complex position. In the positions in which the pawn wins, at most nineteen moves are required to promote the pawn (with optimal play) and at most nine more moves to checkmate, assuming that the pawn was promoted to a queen. In general, the player without the pawn should place their king in the path of the pawn to try to prevent its promotion.

Rule of the square

The most basic rule applies when the pawn can queen unassisted by its king. The rule of the square determines if this is possible. In the depicted position, the pawn is on the fifth square from the queening square (counting the queening square itself). A square of 5×5 squares with the queening square in one corner and the pawn in an adjacent corner can be imagined. (An easy method is to construct the square with a diagonal from the pawn to the last rank.) This square denotes where the Chebyshev distance from the pawn's promotion square is no greater than the number of moves the pawn needs to promote, and thus, if the black king can move into this square, he can catch the pawn, otherwise the pawn wins the race. In this position, if it is Black's move, they can play ...Kb4 and enter the square, catching the pawn. If it is White's move, the pawn advances, the square shrinks to 4×4, and the king cannot move into the square, so the pawn queens. (See Wikibooks – Chess/The Endgame for further discussion on the rule of the square.) Even if the defending king can move inside the square of the pawn, the attacking king may be able to block it, as in the diagram from Alexander Fishbein. :1... Ke4 Moving into the square. :2. Kb4! Kd5 3. Kb5! Kd6 4. Kb6! Kd7 5. Kb7! Kd6 6. a5 Kc5 7. a6 Kb5 8. a7 and the pawn promotes. Note that in some cases, the king can catch a pawn when he is outside the square by creating threats that must be parried, and gain a tempo. In the Réti endgame study (by Richard Réti, 1921), the white king is outside the square of the black pawn, two tempi short of catching the pawn. White can draw, however, by "going after two birds at once".: 1. Kg7! h4 2. Kf6! Kb6 If 2...h3 then 3.Ke7 or 3.Ke6 and the pawns promote together.: 3. Ke5! Kxc6 If 3...h3 then 4.Kd6 h2 5.c7, draw.: 4. Kf4, resulting in a draw.

Key squares

If the defending king is within the "square", then the pawn cannot queen without the help of its own king. The first concept that needs to be introduced is that of the key square, also known as a critical square. A key square is a square such that if White's king occupies it, White can force the pawn to promotion, regardless of where the black king is and regardless of which side is to move, and against any defense (assuming that the black king cannot capture the pawn). The key squares are relative to the position of the pawn. Whether or not the white king can reach a key square depends on the position of the pieces. Of course, even if the white king occupies a key square, accurate play is still required in order to promote the pawn. Note that the key square is in front of the pawn. Endgame expert Yuri Averbakh said, just as a father leads his child across the road rather than pushing the child in front, the king should also lead the pawn to the queening square.

Rook pawn

A rook pawn (on the a-file or h-file) has much less chance of promoting than other pawns. The reason is that if the opposing king can get to any square in front of the pawn, it cannot be driven away from the file, and the pawn cannot queen. Black can always draw if he can reach the c8-square for an a-pawn (pawn on the a-file), or the equivalent f8 for an h-pawn, except for the position in the next diagram, with White to move. Therefore, an advanced rook pawn generally has two key squares: b7 and b8 for an a-pawn, and g7 and g8 for an h-pawn. The key squares are indicated by the black dots in the position in the diagram. If White's king can reach either of the two key squares, he can keep Black's king away and the pawn will promote. If the black king can reach any of the squares marked with a dot or a cross, it stops the pawn. The pawn can also promote in the position on the right (if White is to move), after :1. h7 In practice, however, most of the time the black king can stop a rook pawn because it is usually close enough that the white king cannot prevent it from getting in front of the pawn (or capturing it).

Examples from games

The game Oscar Panno–Miguel Najdorf, Buenos Aires 1968, continued: 59. Kg4 Kc7 60. Kg5 and White won because the white king can reach the key square g7. Black resigned in light of: 60... Kd7 61. Kg6 Ke7 If 61...Ke6, then 62.h4; not 62.Kg7?? because 62...Kf5! wins the pawn.: 62. Kg7 Moving to a key square, the only move to win.: 62... Ke6 63. h4 Kf5 64. h5 The only move to win. The king protects the pawn as it promotes. If Black was to move in this position, he would draw by reaching the f8-square and preventing the white king from getting to a key square, and the pawn cannot promote. This position from a game between Gedeon Barcza and future world champion Bobby Fischer was a draw. (White's 96.Kd2 followed by 97.Kc1 draws.)

Pawns other than rook pawns

Pawns other than rook pawns have a much better chance of promoting. If the pawn is on the second, third, or fourth rank, there are three key squares – the square two squares in front of the pawn and the squares to the left and right of that square. The key squares are indicated by the black dots (for example, see the left-most diagram). If the pawn is on the fifth or sixth rank, there are six key squares: the square in front of the pawn and the squares to the left and right, as well as the square two squares in front of the pawn, and the squares to the left and right of it (see the diagram in the middle). When the pawn is on the seventh rank, the key squares are the squares on the seventh and eighth rank that touch the pawn's square (see the right-most diagram). An easy way to remember the key squares is to note that if the pawn is not beyond the midpoint of the board, there are three key squares that are two ranks ahead. If the pawn is on the fifth or sixth rank there are six key squares on the two ranks in front of the pawn. If the pawn is on the seventh rank, the adjoining squares on the seventh and eighth ranks are key squares. Once White's king occupies a key square he can keep the opposing king from blocking the advance of the pawn, as will be shown below.