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.
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.[1] Nunn covers 100 topics in Understanding Chess Endgames – eight are about this type of endgame.[2]
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.
| Pawn | Max DTC | Percentage | Winning % |
|---|---|---|---|
| a/h | 51 | 26% | 34% |
| b/g | 60 | 31% | 48% |
| c/f | 57 | 29% | 44% |
| d/e | 59 | 15% | 43% |
In his 1958 book Chess Endgames, Nikolay Kopaev gave these general guidelines for when the pawn is on the sixth or seventh rank:
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.
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 Rg8Checks from the front or side do not help Black.
4. d6 Rg7+
5. Kc8 Rg8+
6. Kc7 Rg7+
7. d7and 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:
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. Kb4This 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 Ra1White 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.
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:
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. Kb5The white king must have this file available.
2... Rd8
3. Kc5 Rc8+
4. Kb6! Rd8
5. Rd1! Kf6
6. Kc7 Ra8
7. d5and 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 Kd6Or 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 Rb8and 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. f33.f4 draws after 3...Rd7 or 3...Kc7.
3... Re7+
4. Kf2 Rf7
5. Kg3 etc.,and White wins.
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. Kf7Now 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. Ke2and 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.
See main article: 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.
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 Kb6Other fourth moves by Black are no better. If 4...Rd4+ then 5.Ke5 wins, as the rook cannot stop the pawn. If Black tries a different move, say 4...Re2 then White moves 5.Rc5 and builds a bridge on the fifth rank.
5. Rd1 Kb5
6. Rd5+ Kb6
7. Re5and Black cannot stop the pawn.
It may not be necessary to build a bridge (as in the Lucena position) to win, if the king is on its pawn's promotion square. White wins in this position:
1. Rc2+ Kb7Or 1...Kd6 2.Kd8 Rxe7 3.Rd2+ Ke6 4.Re2+ wins the rook.
2. Rf2 Rh1
3. Kf7 Rh7+
4. Ke6 Rh8
5. Kd7 Rh7
6. Kd8 wins.
Often White will not be able to utilize one of the winning methods. Black has several defensive methods available, depending mainly on the position of the pawn and their king. If the defending king is in front of the pawn and the attacking king and pawn have not yet reached their sixth rank, the Philidor position (or Philidor defense) easily works to secure a draw. If the defending king cannot get in front of the pawn but is not cut off, the short-side defense can be used. If the pawn is a rook pawn or knight pawn, the back-rank defense can be used. The back-rank defense can also be used when the pawn is on other files if the attacking king has not reached the sixth rank. If the king is cut off along a file, the frontal defense may work, depending on the file of the pawn and how far advanced it is.
See main article: Philidor position.
Philidor's position (see the diagram) illustrates an important drawing technique in this endgame. The technique is also known as the third-rank defense and works when the defending king is in front of the pawn and the attacking king and pawn have not reached their sixth rank. Black keeps their rook on their third to keep the white king from reaching that rank. If White advances the pawn to its sixth rank (Black's third rank), then the king is deprived of shelter, so Black moves their rook to the eighth (or seventh) rank, and keeps checking the white king from behind. It is very important that the defender keep their rook on their third rank, and move to the far side of the board after the attacking pawn has moved to its sixth rank. (An exchange of rooks will result in a drawn position, see king and pawn versus king endgame.) See Philidor position for more details.
There are three errors that Black must avoid:
Philidor's defense can also be used with the black rook on the fourth rank, if White's king and pawn have not reached that rank. If this defense is used, the black king should be on the second rank. The principle is the same: Black keeps their rook on the fourth rank, keeping the white king from advancing to that rank. If the pawn advances to that rank, Black moves the rook to the eighth rank and checks the king from behind.
The back-rank defense always works if the pawn is a or and the defending king is in front of the pawn. The defending king blocks the pawn and the rook is on the first rank preventing checks by the rook. In the diagram, Black draws. If 1.g7 then 1...Rb6+ draws, and if 1.Rg7+ then 1...Kh8 draws. White's best attempt is:
1. Kg5 Rc8Waiting passively, also known as the passive defense.
2. Kh6 Rb8
3. Rg7+The only trick for White.
3... Kh8!If 3...Kf8? then 4.Kh7 Rb1 5.Rf7+ Ke8 6.Rf4 and White gets to the Lucena position.
4. Rh7+ Kg8
5. Ra7 Rc8and White makes no progress. The defense fails for other pawns (if the attacking king has reached the sixth rank) because White has another file available to go around the pawn.
If the attacking king has not reached the sixth rank, the defense works for any pawn. In the second diagram, White to move wins by getting their king to the sixth rank so the defending rook can not leave the back rank because of the threat of checkmate. This illustrates how the defense fails for a or :
1. Kg6 Rd8
2. Rh7 Kg8
3. f7+ Kf8
4. Rh8+ Ke7
5. Rxd8 and wins.
If Black is to move in the diagrammed position, they draw with
1... Rb1!which neutralizes the threat of Kg6, because Black can check from behind and there is no immediate threat of checkmate by White. Black checks from behind, as in the Philidor defense.
If neither the pawn or king have reached the sixth rank, Black can normally draw by reaching the Philidor position, above.
Sometimes, the defender's king is in front of the pawn, but the rook cannot get to its third rank to reach the Philidor position. Thus, they have two choices: try to attack from behind, or retreat to the back rank with their rook to guard the mating threats. The diagrams show such back-rank positions. For a (see first diagram) or, if the defending rook is tied down to the back rank, the defender loses:
1. Rg7+ Kf8 (or Kh8)
2. Rh7! Kg8
3. f7+ Kf8
4. Rh8+winning the rook. But the defender can hold the draw with an accurately conducted "active defense" from behind the pawn while it is still on the fifth rank, with the king moving to the short side (see next section).
With a (see second diagram), however, the attacker has no file equivalent to 2.Rh7, so they cannot make progress. Here, the defender should avoid the active defense (attacking the pawn from behind while it is on the fifth with the rook). It fails because their king will be forced to the long side (stepping the other way would lose immediately because of the corner, allowing immediate mate).
The defender can draw against the either way, because most king and pawn versus king positions are drawn with the rook pawn (see).
Not all positions similar to the Lucena position above are wins for the superior side – it depends on the position of Black's rook and king (relative to White's pawn), and which side is to move. In positions such as the position in this diagram, the defending rook must be at least four files away from the pawn on the "long side" for the defense to work (the "checking distance"); otherwise the white king can support its pawn and approach the black rook to drive it away. The black king needs to be on the "short side" so it will not block checks by its own rook.
As an example, Black to move draws in this diagram. The reason is that Black can check the white king from the side with their rook, and the rook is just far enough away from the white king that if it tries to approach the rook to stop the checks, the rook can get behind the pawn and win it, resulting in a drawn position. For example:
1... Ra8+
2. Kd7 Ra7+
3. Kd6 Ra6+
4. Kd5 Ra5+
5. Kc6 Ra6+ If 5...Ra8 6.Ra1! (Either Black takes the rook and the white pawn queens, or it forces the enemy rook off the vital a-file that has "checking distance", the rook moves on the back rank, followed by 7.Kd7, and the pawn promotes.)
6. Kb7 Re6with a draw after winning the pawn, which can no longer be defended by its king.
If White's king and pawn are moved to the left, White wins as in the Lucena position above. With a few exceptions, the defending rook must be at least four over from the pawn for this defense to work (which is why the defending king should go to the short side, to not block checks by their rook).
1... Ra8+1...Rc2 leads to a Lucena position.
2. Kc7 Ra7+
3. Kc8 Ra8+
4. Kb7 Rd8
5. Kc7!and White wins. The rook was too close to the pawn, so White's king could both approach the rook to prevent checks and return to protect the pawn.
1. Kg6This threatens 2.Ra8+ Ke7 3.f6+ driving the black king far from the pawn. (See the Lucena Position next section for White's winning method.) 1...Rb6+ is too late because of 2.f6, forcing Black to retreat to the back rank, which is a loss as shown in the previous section. The point of Philidor's third rank defense is to prevent White from moving the king to the sixth rank before the pawn.
| + Short-side defense, less-advanced pawn |
Black's defense is:
1... Rf1Tarrasch rule, rook behind pawn.
2. Kf6 (second diagram)2.Ra8+ Ke7 and now the black rook stops 3.f6+.
2... Kg8!Going to the short side is vital, as will become clear.
3. Ra8+ Kh7
4. Rf8Other moves make no progress because of Black's obeying the Tarrasch rule. E.g. 4.Ke6 Kg7 and 5.f6+ is impossible. The main move protects the pawn and threatens 5.Ke7 followed by f6.
4...Ra1!Now Black threatens to check from the side to keep White from making any progress. Black needs space to do this, which is why the king must move out of the way to the short side. There must be at least three files between Black's rook and the pawn, otherwise White's king can protect White's pawn while attacking Black's rook and gain time necessary to advance the pawn.
5. Re8One try, to use the rook to block the checks from the side.
5... Rf1!Black moves behind the pawn again, so 6.Ke6 is answered by 6...Kg7, as per note to move 4.
If the black king went to the long side, Black would not have the resource of checking from the side. For example, from the second diagram above, where 2...Kg8! draws as shown above:
2... Ke8?
3. Ra8+ Kd7
4. Rf8! Rh1
5. Kg7 Ke7There is no room to check on the side. If 5...Rg1+ then 6.Kf7 followed by f6.
6. f6+The point of 4.Rf8.
6... Kd76...Ke6 7.Re8+ Kd7 8.Re2 and converts to Lucena position, next section.
7. Kf7followed by Ra8 then Ra2-d2+ (or any other safe check on the d-file). After this, and the same if Black prevents the check by placing their own rook on the d-file, White plays Kg7 Rg(any)+; Kf8 then f7, reaching the Lucena position.
If the pawn is a central pawn, going to the long side with the defending king will sometimes give the rook just enough checking distance if it is on the rook file on the opposite side of the pawn. Defending this way is a far more arduous task, so moving the defending king to the short side is always recommended. With the defending rook three files over from the pawn, the attacker usually wins, but there are exceptions, depending on the location of the attacking rook.
In the diagram, Black draws:
1... Re8!
2. Kd6 Rb8!If 2...Rg8 then 3.Ra1!. If 2...Kf6 then 3.Ra1! Rb8 4.Rf1+ Kg7 5.Kc6 Ra8 6.Ra1, a winning position.
3. Kd7 Re8and White can not make any progress.
The Frontal Defense is a way that Black may keep White from getting to the Lucena position, even if the defending king is cut off from the pawn's file. Black's rook is well-placed on its first and can check the white king or offer itself for exchange when the resulting king and pawn versus king endgame is a draw. The farther back the pawn is, the more likely the defense is to be successful. To have good drawing chances, there should be at least three ranks between the pawn and the defending rook (called the rule of three). The file of the pawn matters too: a gives the best winning chances, followed by a, followed by a, with a having little chance of winning.
If White is to move in the diagram, Black draws by using the frontal defense:
1. Kh4 Rh8+!
2. Kg5 Rg8+
3. Kh5 Rh8+
4. Kg6 Rg8+
5. Kh5 Rh8+and White cannot make any progress.
If Black to move in this position, they have an alternative drawing method that requires knowledge of the king and pawn versus king endgame:
1... Rf8 To bring the king over to the pawn.
2. Rxf8 Kxf8
3. Kf4 Kg8! Avoids losing the opposition. 3.Kh4 is met the same way.
4. Kf5 Kf7 or 4.Kg5 Kg7, and the position is a draw.
The frontal defense may or may not work for and, even if there are three ranks between the pawn and the defending rook. In the diagram from Emms, White to move wins:
1. Kg4! Rg8+
2. Kh5 Rf8
3. Kg5 Rg8+
4. Kh6 Rf8
5. Re4! Kd6
6. Kg7 Rf5
7. Kg6 Rf8
8. f5and White will reach the Lucena position.
Black to move in that position draws, by reaching a drawn king and pawn versus king endgame position:
1... Re8
2. Rxe8 Kxe8
3. Ke4 Kf8
4. Ke5 Ke7
Black to move in that position also draws with 1... Kd6, getting the king to a favorable position.
Endings with a rook pawn arise frequently because they are more likely to be the last remaining pawn. If the pawn is a rook pawn, the chances of a draw are much greater. Even the equivalent of the Lucena position is no guarantee of success (it depends on the location of the white rook and who is to move). These endings are more likely to be a draw because (1) the pawn can protect the king from checks from the rear only, and not from the side, and (2) the edge of the board reduces the king's mobility in trying to support the pawn.
With a rook pawn, usually in actual play the defending rook or king is able to get in front of the pawn. If the defending king gets in front of the pawn, the game is a draw. If the defending rook gets in front of the pawn, the result depends on which king arrives on the scene first.
The attacking king or rook may be in front of the pawn.
In this diagram, the only way for White to make progress is to get their rook to b8, but this allows the black king to get to the c-file and draw.
1. Rh2 Kd7
2. Rh8 Kc7!
3. Rb8 Rc1
4. Rb2 Rc3!This is the simplest way for Black. Now there is no way to force the black king away from the c-file.
5. Rb7+ Kc8
6. Rg7 Rc1and Black draws.
If the black king is cut off by four or more files, White wins, as in this diagram:
1. Rc3! Ke7
2. Rc8 Kd6
3. Rb8 Ra1
4. Kb7 Rb1+
5. Kc8 Rc1+
6. Kd8 Rh1
7. Rb6+ Kc5
8. Rc6+! Kd5
9. Ra6and White wins.
In this position, the black king needs to get to one of the marked squares in order to draw. If it gets to one of the squares marked with "x", the king can move next to the pawn and the rook can the pawn for a draw. Otherwise, the king needs to stay on the squares marked with dots: g7 and h7. The reason is that if the black king is on another rank, the white rook can check and then the pawn promotes and wins. For example, if the black king were on f6 instead, with White to move, 1.Rf8+ followed by 2.a8=Q wins. Also, the black king needs to be on g7 or h7 rather than d7, e7, or f7. If it were White's move in this position, White wins by 1.Rh8 Rxa7 (otherwise the pawn promotes and wins) 2.Rh7+, skewering the rook. If the black king is on g7 or h7 and the white king approaches the pawn (to protect it while the rook moves out of the way), the black rook will check from behind and the king has no cover from the checks.
The Vančura position (see diagram) is a drawing position with a rook and rook's pawn versus a rook, when the pawn is not beyond its sixth rank, and the stronger side's rook is in front of the pawn. It was studied by Josef Vančura (1898–1921), published in 1924. Black's rook keeps attacking the pawn from the side from some distance away, while preventing the white king from finding cover from checks. The black king must be on the opposite side of their rook as the pawn to not block the attacks. The black rook moves behind the pawn as soon as the pawn moves up to its seventh rank. Also, Black's king must be near the corner on the opposite side of the board if the pawn advances to its seventh rank so the white rook cannot check the black king and then support the advance of the pawn, or sacrifice its pawn to skewer Black's king and rook on the seventh rank, as in the section above.
1. Kb5Protecting the pawn in order to free the rook to move. If 1.a7 Ra6! 2.Kb5 Ra1 3.Kb6 Rb1+ 4.Kc7 Rc1+ 5.Kd7 Ra1, and White cannot win. Note that if Black's king were on g6 there would follow 2.Rg8+ with 3.a8=Q, and if it were on f7 White would win with 2.Rh8! Rxa7 3.Rh7+.
1... Rf5+!
2. Kc6 Rf6+!An important square for the rook. Black now checks on the f-file and aims to maintain a sideways attack on the pawn.
3. Kd5 Rf5+
4. Ke6 Rf6+
5. Ke5 Rb6 Maintaining sideways contact with the pawn.
6. Kd5 Rf6
7. Kd4 Rb6 But not 7...Rf4+? 8.Ke5! and White wins.
8. Kc5 Rf6
9. Ra7+ Or 9.a7 Ra6! with a draw.
9... Kg6
10. Ra8 Kg7and White cannot win. The white king cannot advance because of the checks and the pawn cannot advance because the black rook gets behind the pawn.
In Shakhmaty v SSSR in 1950, Peter Romanovsky published a drawing zone (see diagram). If Black is to move and the white king is on one of the marked squares, Black draws by reaching the Vančura position. Otherwise White wins.
Cecil Purdy gives the most common type of rook endgame as one with a rook and rook pawn versus a rook, with the rook in front of its pawn.
| + Purdy's most common rook and pawn endgame |
1... Ke7
2. Rb8 R-any
3. Kb7 Rb1+
4. Ka8! R-any
5. a7and White wins. They can force their king out by Kb7 or if the black rook prevents that by going to the seventh rank, then Rh8 and Kb8.
In this diagram, White to move wins, starting with 1.Ke2. Black to move draws.The positions discussed above are somewhat idealized, but they are fundamental to practical play. Here are some examples of this endgame from master games.
| + Larsen vs. Browne, 1982 |
The game Bent Larsen–Walter Browne, Las Palmas 1982,[3] illustrates an alternate winning method with a knight pawn. A variation of moves would have resulted in the "building a bridge" method.
65... Rg7+ 66. Kf4 Rf7+ 67. Kg5 Ke5 68. g4 Rf8 69. Kh5 Rf7 70. g5 Kf5 71. Rh8 Ke6 72. Re8+ Kf5 73. g6 Ra7 74. Rf8+ Ke6 75. Rf1 Ra2 76. Kh6 Ke7 77. g7 Rh2+ 78. Kg6 Rg2+ 79. Kh7 Rh2+ 80. Kg8 (second diagram) Ra2Or if 80...Rh3, then 81.Re1+ Kd7 82.Re4 Rh2 83.Kf7 Rf2+ 84.Kg6 Rg2+ 85.Kf6 Rf2+ 86.Kg5 Rg2+ 87.Rg4 and White will win by building a bridge.
81. Rh1
60... Re2! (cutting the white king off) 61. Kf3 Re7 62. Kf2 Kc6 63. Kf3 Kb6 64. Rd5 c3 65. Rh5 c2 66. Rh1 Rc7 67. Rc1 Kb5 68. Ke2 Kb4 69. Kd2 Kb3 70. Rh1 Kb2! 0–1
Black can not reach the Philidor position, but still draws.
45... Rf4!! 46. Ra8+ Kh7 47. Ke6 Kg7 48. Ra7+ Kf8 49. Kf6 Kg8 50. Ra8+ Kh7 51. Rf8 Ra4! 52. Rf7+ Kg8 53. Re7 Kf8 54. Re6 Ra7 55. Rb6 Rf7+ 56. Kg5 Ra7 57. f6 Kf7 ½–½
95... Rb4+ 96. Kg3 Kh5 97. Ra3 Rg4+ 98. Kh3 Rh4+ 99. Kg3 Rb4 100. Re3 Rb5 101. Ra3 g4 102. Rc3 Kg5 103. Ra3 Rc5 ½–½
There can be subtle differences in positions that make the difference between a win and a draw. Two examples of this are shown in the diagrams.
There are exactly 209 positions of reciprocal zugzwang among rook and pawn versus rook endgames. All of them were tabulated and published.[4] [5] [6] The full list is available online.[7] Some of the zugzwangs are easy to understand (see position at the middle); some requires up to 54 moves to win. The position at left is a position that could have occurred in the 1961 game between Viacheslav Kalashnikov and the young Anatoly Karpov.[8] White to move in this position draws, but Black to move loses. Karpov's 49th move in the actual game avoided the zugzwang and the game was drawn.
A rook and two pawns generally win against a rook, but there are exceptions. In actual games, the side with the pawns wins 82% of the time.