The rook and pawn versus rook endgame is a fundamentally important, widely studied chess endgame. Precise play is usually required in these positions. With optimal play, some complicated wins require sixty moves to either checkmate, capture the defending rook, or successfully promote the pawn. In some cases, thirty-five moves are required to advance the pawn once.

The play of this type of ending revolves around whether or not the pawn can be promoted, or if the defending rook must be sacrificed to prevent promotion. If the pawn promotes, that side will have an overwhelming advantage. If the pawn is about to promote, the defending side may give up their rook for the pawn, resulting in an easily won endgame for the superior side (a basic checkmate). In a few cases, the superior side gives up their rook in order to promote the pawn, resulting in a winning queen versus rook position (see ).

A rule of thumb (with exceptions) is: . The side with the pawn can cut off the opposing king or strive for the Lucena position, which is a win. The defender can aim for the Philidor position (which is a draw) or try to set up one of the other defensive techniques that draw. A rook and two pawns usually win against a rook, but there are plenty of exceptions.

Importance Endings with rooks and any number of pawns are the most common type to occur in games, occurring in about 8 to 10 percent of all games. A majority of rook and pawn endings with more pawns have the potential of being reduced to this type of endgame (rook and one pawn versus rook). John Nunn wrote a 352-page book about this ending, Secrets of Rook Endings. Volume 2 of the Encyclopedia of Chess Endings devotes 92 pages to the analysis of 428 positions of this type. André Chéron wrote over 150 pages analyzing 120 positions of this endgame in their famous book Lehr- und Handbuch der Endspiele. In 100 Endgames You Must Know by Jesús de la Villa, 17 are of this type."[T]he study of rook plus pawn vs. rook is the first and essential step to understanding positions with more pawns on the board." de la Villa, 2008, p. 123. "[The Philidor Position] is perhaps the most important one in endgame theory." de la Villa, 2008, p. 125. In Fundamental Chess Endings, Karsten Müller and Frank Lamprecht say that the Philidor Position is "the most important position in the whole book" (emphasis in the original). Nunn covers 100 topics in Understanding Chess Endgames – eight are about this type of endgame.The ending of rook and pawn versus rook is one of the basic endings which arises most often in practice, and it is also fundamental for a general understanding of rook endings. Nunn 2009, p. 106

This table summarizes results from games compiled from several game databases, where this position was reached. "Max DTC" is the maximum number of moves in depth to conversion, either a checkmate or conversion to a winning endgame via promotion of the pawn or capture of the opposing rook. +Games with rook and pawn versus rookPawnMax DTCPercentageWinning %a/h5126%34%b/g6031%48%c/f5729%44%d/e5915%43%

Terminology In the following discussion and positions, assume that the side with the pawn is White. White will be attempting to win and Black will be attempting to draw. are counted from that player's side of the board. Thus, "the rook's third rank" would be the third rank counting from that player's side of the board. The ranks for the white pieces correspond to the ranks in algebraic notation, whereas the ranks for the black pieces are reversed. In these positions with one pawn, the pawn's file divides the board into a short side and a long side, in which the long side consists of more files than the short side. A pawn is referred to by the on which it stands: a rook pawn is on the a- or h-file, a knight pawn is on the b- or g-file, a bishop pawn is on the c- or f-file. A central pawn is a or a , on the d- or e-file. When designating a position as a win or a draw, optimal play by both sides is assumed.

Pawn on the sixth or seventh rank In his 1958 book Chess Endgames, Nikolay Kopaev gave these general guidelines for when the pawn is on the sixth or seventh rank: When the black king is cut off two or more files from the pawn, White always wins. If the black king is on the long side of the pawn and their rook is on the short side, White wins with very few exceptions. (The long side is the side with more to the side of the board – the short side is the side with fewer files). If the pawn is on the seventh rank, the only defense involves checks from the side. If the pawn is on the sixth rank, a defense of checks from the rear is possible. The defense of checking from the side normally requires three empty files between the pawn and the black rook. Sometimes it is possible with only two files when the pawn is on the seventh rank. In order for a defense of checking from behind to be successful, the white king must be behind the pawn, not in front of it. There are tactical possibilities: (1) deflecting the black rook, and (2) creating a shelter for the white king.

Winning methods In order to force a win with the extra pawn, normally the black king must be cut off from the pawn by the white rook along a or , and that is not always sufficient.

Black king is cut off along a rank

If the black king is cut off from the pawn along a rank (as in the diagram), White wins easily if the king is behind the pawn: 1. Kd6 Rd8+ 2. Ke6 Re8+ 3. Kd7 Rg8 Checks from the front or side do not help Black. 4. d6 Rg7+ 5. Kc8 Rg8+ 6. Kc7 Rg7+ 7. d7 and the pawn will soon promote.

When cutting the defending king off by a rank, a perfect cut is when the pawn is on the same rank as the defending king. An imperfect cut is when the king is on the rank ahead of the pawn. These general rules apply: The defending king should be cut off on a rank on the long side of the pawn. Otherwise, the position is not dangerous for the defense if the defending rook is on the long side. With a perfect cut, the position is always won with a or on any rank. A wins if it is on the fourth rank or beyond. With an imperfect cut, the position is a draw if the defending rook is on the file adjacent to the pawn. In addition, the defense has more possibilities against a central pawn.

In this position, White has a perfect cut and wins: 1... Ra8 2. Rc6 Rb8 3. Ra6 Kd5 4. Ka4! Kc4 5. Rc6+! Kd5 6. b5 Ra8+ 7. Kb4 This is the same position but advanced one rank. Now the process is repeated: 7... Rb8 8. Rc7 Kd6 9. Ra7 Kd5 10. Ka5 Kc5 11. Rc7+ Kd6 12. b6 Ra8+ 13. Kb5 Ra1 White threatened Rh7, b7, and Kb6 so Black tries checks from the rear. However, play will soon lead to a Lucena position (see below), which easily wins for White.

Black king is cut off from the pawn's file When the black king is cut off from the pawn's file the outcome depends on where the black king is in relation to the pawn. Black's king is often cut off from the pawn along a file. Some general rules (with exceptions) are:

If the pawn is a rook pawn, the position is usually a draw. If the pawn is on the fifth rank (or sixth or seventh rank) with its king near, and the black king is cut off from the pawn's file, White has a won position. If the pawn is on the third or fourth rank, (a) if it is a or , White always wins if the black king is cut off by two files for a fourth rank pawn and three files for a third rank pawn (see "The Rule Of Five" below) (i.e. White's rook is two files over from their pawn and the black king is on the other side), and (b) if the pawn is a , White always wins if the black king is cut off by three files. If the pawn is on the second rank and the black king is on the fourth or fifth rank, White wins only if the opposing king is cut off five files from the pawn. In some cases White wins even if the black king is closer.

Rule of five

The rule of five is for positions in which the pawn is protected and the opposing king is cut off by files: For example, in the diagram, white wins by:

1. Kc4 Rc8+ 2. Kb5 The white king must have this file available. 2... Rd8 3. Kc5 Rc8+ 4. Kb6! Rd8 5. Rd1! Kf6 6. Kc7 Ra8 7. d5 and White will win.

The position by Chéron is basically the same, except moved over two files. Now the white king has less room to maneuver on the left of the pawn's file, and Black can prevent the advance of the pawn and draw. If White starts with 1. Ka4, the rook checks the king, and the king is forced back to b3. White can try:

1. Rd4 Ke5 2. Kc3 Rc8+ 3. Rc4 Rb8 4. Rc6 Kd5 5. Ra6 Rc8+ 6. Kb3 Rc6! 7. Ra8 Kd6 Or 7.Ra7 Rc1, and the black king reaches the pawn's file, for a draw. Another try for White is: 1. Rd2 Ke5 2. Rd7 Ke6 3. Rc7 Kd6 4. Rc5 Kd7 5. Ka4 Ra8+ 6. Ra5 Rb8 7. Ra7+ Kc6 8. Ka5 Rb5+ 9. Ka4 Rb8 and the position is drawn. If the pieces are moved one file to the right, White has a win.

In the discussion above about the defending king being cut off by files, it is assumed that the defending rook is already in position to check the attacking king along files (usually from its first rank). In this position by José Capablanca, White wins because the white pawn can reach its fourth rank before the black rook can check along files. If the black rook were already at and it were Black's move, Black would draw by checking the king and by playing ...Rf8 when the white king moves to . With White to move in the diagrammed position:

1. Rd1 Rh8 2. f4 Re8+ 3. Kf3 Rf8 4. Kg4 Rg8+ 5. Kh5 Rh8+ 6. Kg6 etc., and White will win. With Black to move,

1... Kc6 2. Rd8 Rh7 3. f3 3.f4 draws after 3...Rd7 or 3...Kc7. 3... Re7+ 4. Kf2 Rf7 5. Kg3 etc., and White wins.

Simple method for bishop pawns and central pawns

There is a simple way of winning if the pawn is a bishop pawn or central pawn (i.e. on the c-, d-, e-, or f-file) and its king can reach the promotion square of the pawn.

In the diagram, 1. Rc2+ would start the process of winning as in the Lucena position (below). However, White also wins more easily by: 1. Rh2 Rf3 2. Rh8 Rf1 3. Rf8 Re1 4. Kf7 Now either 4... Kd7 5. e8=Q+ and White wins easily, or the white king can approach the black rook on the two files next to the pawn's file until it can no longer check: 4... Rf1+ 5. Kg6 Rg1+ 6. Kf5 Rf1+ 7. Kg4 Rg1+ 8. Kf3 Rf1+ 9. Ke2 and the black rook can no longer attack, and the pawn promotes.

This method does not work for rook pawns (e.g. a- and h-files) or knight pawns (e.g. b- and g-files), because the white king does not have room to maneuver. However, the Lucena position (below) is a win for White if the pawn is not a rook pawn.

Lucena position

The Lucena position is one of the most famous and important positions in chess endgame theory. It is a win for the side with the pawn. The essential characteristics are that White's king is on the queening square in front of their pawn, the pawn is on the - through -files, the black rook cuts off White's king from escaping away from the black king, and the Black king is cut off on a file.

White wins in the position in the diagram by 1. Rd1+ forcing the black king one farther away, then bringing their rook to the fourth to make a "bridge" to protect the king, then bringing out the king, which will be checked by Black's rook. White maneuvers their king to the fifth rank (without giving up the pawn) and then when the black rook checks, White interposes their rook and has a winning position. See Lucena position for more details.

Defending rook prevents the bridge

If the defending rook is on the superior side's fourth rank, it prevents the rook from making a bridge on that rank. In that case, the win is straightforward. 1. Rc1+ Kb7 2. Kd7! The black rook is not far enough away from the white king to keep safely checking. 2... Rd4+ 3. Ke6 Re4+ 4. Kd6 Kb6