The exchange (chess)
Encyclopedia
The exchange in chess
Chess
Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...

 refers to a situation in which one player loses a minor piece (i.e. a bishop
Bishop (chess)
A bishop is a piece in the board game of chess. Each player begins the game with two bishops. One starts between the king's knight and the king, the other between the queen's knight and the queen...

 or knight
Knight (chess)
The knight is a piece in the game of chess, representing a knight . It is normally represented by a horse's head and neck. Each player starts with two knights, which begin on the row closest to the player, one square from the corner...

) but captures the opponent's rook
Rook (chess)
A rook is a piece in the strategy board game of chess. Formerly the piece was called the castle, tower, marquess, rector, and comes...

. The side which wins the rook is said to have won the exchange, while the other player has lost the exchange, since the rook is usually more valuable. Alternatively, the side that has won the rook is up the exchange, and the other player is down the exchange. The opposing captures often happen on consecutive moves, although this is not strictly necessary. It is generally detrimental to lose the exchange, although occasionally one may find reason to purposely do so; the result is an exchange sacrifice (see below). The minor exchange is an uncommon term for the exchange of a bishop and knight.

Note that the exchange differs from the more general "exchange
Exchange (chess)
In the tactics and strategy in the board game of chess, an exchange or trade of chess pieces is series of closely related moves, typically sequential, in which the two players capture each others pieces. Any types of pieces except the kings may possibly be exchanged, i. e. captured in an...

" or "an exchange", which refers to the loss and subsequent gain of arbitrary pieces, e. g. to "exchange queens" would mean that each side's queen is captured.

Value of the exchange

The value of the exchange (i.e. the difference between a rook and a minor piece) has been considered for decades. Siegbert Tarrasch
Siegbert Tarrasch
Siegbert Tarrasch was one of the strongest chess players and most influential chess teachers of the late 19th century and early 20th century....

 put its value as 1½ pawns
Pawn (chess)
The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

 in the endgame, but not for the opening
Chess opening
A chess opening is the group of initial moves of a chess game. Recognized sequences of opening moves are referred to as openings as initiated by White or defenses, as created in reply by Black. There are many dozens of different openings, and hundreds of named variants. The Oxford Companion to...

 or the first part of the middlegame. That is widely accepted today, but Jacob Sarratt
Jacob Sarratt
Jacob Henry Sarratt was one of the top English chess players of the late 18th and early 19th century. Sarratt was renowned as a player and author and adopted the title "Professor of Chess" . He was the first professional player to teach chess in England...

, Howard Staunton
Howard Staunton
Howard Staunton was an English chess master who is generally regarded as having been the world's strongest player from 1843 to 1851, largely as a result of his 1843 victory over Saint-Amant. He promoted a chess set of clearly distinguishable pieces of standardised shape—the Staunton pattern—that...

, and José Capablanca felt that the exchange was worth two pawns. Tigran Petrosian
Tigran Petrosian
Tigran Vartanovich Petrosian was a Soviet-Armenian grandmaster, and World Chess Champion from 1963 to 1969. He was nicknamed "Iron Tigran" due to his playing style because of his almost impenetrable defence, which emphasised safety above all else...

 thought that one pawn was the right value. Wilhelm Steinitz
Wilhelm Steinitz
Wilhelm Steinitz was an Austrian and then American chess player and the first undisputed world chess champion from 1886 to 1894. From the 1870s onwards, commentators have debated whether Steinitz was effectively the champion earlier...

 said that a rook is slightly better than a knight and two pawns but slightly worse than a bishop and two pawns . Cecil Purdy
Cecil Purdy
Cecil John Seddon Purdy was an Australian chess International Master and inaugural World Correspondence Chess champion. Purdy earned the Grandmaster title at Correspondence Chess in 1953...

 said that the value depends on the total number of pawns on the board. The reason is that when there are many pawns, the rooks will have limited mobility because there will not be open files. The exchange is barely worth 1½ points when there are 14 or more pawns on the board. Only when there are ten or fewer pawns may the exchange be worth 2 points . Purdy gave the value as 1½ points in the opening and increasing to 2 points in the endgame. In the middlegame the value would be closer to 1½ than to 2 . Edmar Mednis
Edmar Mednis
Edmar John Mednis was an American International Grandmaster of chess born in Riga, Latvia. He was also a popular and respected chess writer.-Biography:...

 gave the value as 1½ in the endgame . Max Euwe
Max Euwe
Machgielis Euwe was a Dutch chess Grandmaster, mathematician, and author. He was the fifth player to become World Chess Champion . Euwe also served as President of FIDE, the World Chess Federation, from 1970 to 1978.- Early years :Euwe was born in Watergraafsmeer, near Amsterdam...

 put the value at 1½ in the middlegame and said that two pawns are more than sufficient compensation for the exchange . Larry Kaufman
Larry Kaufman
Lawrence C. "Larry" Kaufman is a Grandmaster of chess. He is also a mathematics professor and currently lives in Potomac, Maryland. In 2008, as an International Master, Kaufman won the World Senior Championship which automatically earned him the Grandmaster title.A long time researcher in...

's computer research puts the value as 1¾ pawns, but only 1¼ pawns if the player with the minor piece has the bishop pair . Hans Berliner
Hans Berliner
Hans Jack Berliner , a Professor of , is a former World Correspondence Chess Champion, from 1965–68. He is a Grandmaster of Correspondence Chess, and an International Master for over-the-board chess. He directed the construction of the chess computer HiTech. Berliner is also a chess writer.-Life...

 puts the difference between a rook and knight as 1.9 pawns and the difference between a rook and a bishop as 1.77 pawns . In practice, one pawn may be sufficient compensation for the loss of the exchange, whereas two pawns almost always is .

In the endgame

In the middlegame, the advantage of an exchange is usually enough to win the game if the side with the rook has one or more pawns. In an endgame without pawns, the advantage of the exchange is normally not enough to win (see pawnless chess endgame). The most common exceptions when there are no pawns are (1) a rook versus a bishop in which the defending king is trapped in a corner of the same color as his bishop, (2) a knight separated from its king that may be cornered and lost, and (3) the king and knight are poorly placed .

In the endgame of a rook and a pawn versus a knight and a pawn, if the pawns are passed
Passed pawn
In chess, a passed pawn is a pawn with no opposing pawns to prevent it from advancing to the eighth rank, i.e. there are no opposing pawns in front of it on the same file nor on an adjacent file. A passed pawn is sometimes colloquially called a passer...

 the rook is much stronger and should win. If the pawns are not passed, the side with knight has good drawing
Draw (chess)
In chess, a draw is when a game ends in a tie. It is one of the possible outcomes of a game, along with a win for White and a win for Black . Usually, in tournaments a draw is worth a half point to each player, while a win is worth one point to the victor and none to the loser.For the most part,...

 chances if its pieces are well-placed .

In the endgame of a rook and a pawn versus a bishop and pawn, If the pawns are on the same file, the bishop has good chances to draw if the pawns are blocked and the opposing pawn is on a square the bishop can attack; otherwise the rook usually wins. If the pawns are passed the rook normally wins. If the pawns are not passed and are on adjacent files, it is difficult to assess but the bishop may be able to draw .
In an endgame with more pawns on the board (i.e. a rook and pawns versus a minor piece with the same number of pawns) the rook usually wins . This position is typical. The superior side should remember these things:
  1. the main idea is to get the king through to capture opposing pawns
  2. force as many opposing pawns as possible onto the same color square as the bishop
  3. some pawn exchanges may be necessary to open files, but keep pawns on both sides of the board
  4. try to keep the position unbalanced. A passed pawn almost immediately becomes a winning advantage .


If the minor piece has an extra pawn (i.e. one pawn for the exchange), the rook should win, but with difficulty. If the minor piece has two extra pawns, the endgame should be a draw
Draw (chess)
In chess, a draw is when a game ends in a tie. It is one of the possible outcomes of a game, along with a win for White and a win for Black . Usually, in tournaments a draw is worth a half point to each player, while a win is worth one point to the victor and none to the loser.For the most part,...

 .

The exchange sacrifice

An exchange sacrifice occurs when one player gives up a rook for a minor piece. It is often used to destroy the enemy pawn structure
Pawn structure
In chess, the pawn structure is the configuration of pawns on the chessboard. Since pawns are the least mobile of the chess pieces, the pawn structure is relatively static and thus largely determines the strategic nature of the position.-General observations:Weaknesses in the pawn structure, such...

 (as in several variations of the Sicilian Defence
Sicilian Defence
The Sicilian Defence is a chess opening that begins with the moves:The Sicilian is the most popular and best-scoring response to White's first move 1.e4...

 where Black captures a knight on c3 with a rook), to establish a minor piece on a strong square (often threatening the enemy king), to improve one's own pawn structure (creating, for example, connected
Connected pawns
In chess, connected pawns are two or more pawns of the same color on adjacent files, as distinct from isolated pawns. These pawns are instrumental in creating pawn structure because, when diagonally adjacent, like the two rightmost white pawns, they form a pawn chain, a chain where the one behind...

 passed pawn
Passed pawn
In chess, a passed pawn is a pawn with no opposing pawns to prevent it from advancing to the eighth rank, i.e. there are no opposing pawns in front of it on the same file nor on an adjacent file. A passed pawn is sometimes colloquially called a passer...

s such as in A Yurgis vs. Botvinnik, 1931), or to gain time for development. The exchange sacrifice contrasts with other sacrifices
Sacrifice (chess)
In chess, a sacrifice is a move giving up a piece in the hopes of gaining tactical or positional compensation in other forms. A sacrifice could also be a deliberate exchange of a chess piece of higher value for an opponent's piece of lower value....

 in that during the early-middle to middle game the board is sufficiently crowded to where the rook is not as effective as an active knight or a good bishop, this is why such exchange sacrifices happen usually from moves 20 to 30, and rarely occur in the later moves. When they do occur in the endgame, it is usually to create and promote
Promotion (chess)
Promotion is a chess rule describing the transformation of a pawn that reaches its eighth rank into the player's choice of a queen, knight, rook, or bishop of the same color . The new piece replaces the pawn on the same square and is part of the move. Promotion is not limited to pieces that have...

 a passed pawn
Passed pawn
In chess, a passed pawn is a pawn with no opposing pawns to prevent it from advancing to the eighth rank, i.e. there are no opposing pawns in front of it on the same file nor on an adjacent file. A passed pawn is sometimes colloquially called a passer...

 . Subsequently, the relative importance of the pieces might be different than the standardized Chess piece relative value system and takes advantage of the fluctuating values of the pieces during the progression of the game. The sacrifice might also be used to increase the influence of ones own minor pieces by eliminating opposition from their counterparts (such as in the Petrosian versus Spassky game below, where even a double exchange sacrifice was successful). A common example of this idea is the elimination an opponent's bishop, with the expectation that in doing so one's own bishop will increase in power from being unopposed on the color squares in which it resides. There is often more dynamic play and positional considerations such as pawn structure or piece placement compared to sacrifices due to a mating attack or a pawn sacrifice to gain the initiative. Sometimes the exchange can be sacrificed purely on long term positional objectives, as frequently demonstrated by former world champion Tigran Petrosian
Tigran Petrosian
Tigran Vartanovich Petrosian was a Soviet-Armenian grandmaster, and World Chess Champion from 1963 to 1969. He was nicknamed "Iron Tigran" due to his playing style because of his almost impenetrable defence, which emphasised safety above all else...

.

Sokolov vs. Kramnik

In this 2004 game between Ivan Sokolov
Ivan Sokolov
Ivan Sokolov is a chess grandmaster born in Jajce, SFR Yugoslavia, who currently resides in the Netherlands. Sokolov won the 1988 Yugoslav Championship....

 and World Champion Vladimir Kramnik
Vladimir Kramnik
Vladimir Borisovich Kramnik is a Russian chess grandmaster. He was the Classical World Chess Champion from 2000 to 2006, and the undisputed World Chess Champion from 2006 to 2007...

, White gave up the exchange for a pawn in order to create two strong connected
Connected pawns
In chess, connected pawns are two or more pawns of the same color on adjacent files, as distinct from isolated pawns. These pawns are instrumental in creating pawn structure because, when diagonally adjacent, like the two rightmost white pawns, they form a pawn chain, a chain where the one behind...

 passed pawns. The game continued:
33. Rxc7! Qxc7
34. Rxf6 Rxf6
35. Qxf6 Rf8

and White won on move 41 .

Reshevsky vs. Petrosian

Tigran Petrosian
Tigran Petrosian
Tigran Vartanovich Petrosian was a Soviet-Armenian grandmaster, and World Chess Champion from 1963 to 1969. He was nicknamed "Iron Tigran" due to his playing style because of his almost impenetrable defence, which emphasised safety above all else...

, the World Champion
World Chess Championship
The World Chess Championship is played to determine the World Champion in the board game chess. Men and women of any age are eligible to contest this title....

 from 1963–1969, was well known for his especially creative use of this device. He once responded (only half jokingly), when asked what was his favourite piece, as saying "The rook, because I can sacrifice it for minor pieces!" In the game Reshevsky
Samuel Reshevsky
Samuel "Sammy" Herman Reshevsky was a famous chess prodigy and later a leading American chess Grandmaster...

 versus Petrosian at the 1953 Candidates Tournament
Candidates Tournament
The Candidates Tournament is a chess tournament organized by the world chess federation FIDE since 1950, as the final contest to determine the challenger for the World Chess Championship...

 in Zurich, he sacrificed the exchange on move 25, only for his opponent to sacrifice it in return on move 30. This game is perhaps the most famous and most frequently taught example of the exchange sacrifice.

There are no open files in this position for the rooks to exploit. Black sacrificed the exchange with
25... Re6!!.

With the rook not on e7, the black knight will be able to get to a strong outpost
Outpost (chess)
An outpost is a square which is protected by a pawn and which cannot be attacked by an opponent's pawn. In the figure to the right, c4 is an outpost, occupied by White's knight...

 on d5. From there the knight will be attacking the pawn on c3, and if the white bishop on b2 does not move to d2, it will be of little use. In addition, it will be practically impossible to break Black's defense on the white squares. The next few moves were:
26. a4?! Ne7!
27. Bxe6 fxe6
28. Qf1! Nd5
29. Rf3 Bd3
30. Rxd3 cxd3

The game was drawn on move 41 .

Petrosian vs. Spassky

In the tenth game from the 1966 World Chess Championship
World Chess Championship 1966
The 1966 World Chess Championship was played between Tigran Petrosian and Boris Spassky in Moscow from April 9 to June 9, 1966. Petrosian won.-Qualification:-The World Championship match:The match was played as best of 24 games...

 between defending champion Tigran Petrosian and challenger Boris Spassky
Boris Spassky
Boris Vasilievich Spassky is a Soviet-French chess grandmaster. He was the tenth World Chess Champion, holding the title from late 1969 to 1972...

 contained two exchange sacrifices by White. Black had just moved
20... Bh3?! (first diagram)

White responded with an exchange sacrifice:
21. Ne3!

White had no choice: 21. Rf2? Rxf4 22. Rxf4 Qg5+, etc. The game continued:
21... Bxf1?
22. Rxf1 Ng6
23. Bg4! Nxf4?! (second diagram)

And now a second exchange sacrifice:
24. Rxf4! Rxf4

Black is helpless, despite being two exchanges ahead. White won back an exchange on move 29. On move 30 White forced the win of the other rook and the exchange of queens
Queen (chess)
The queen is the most powerful piece in the game of chess, able to move any number of squares vertically, horizontally, or diagonally. Each player starts the game with one queen, placed in the middle of the first rank next to the king. With the chessboard oriented correctly, the white queen starts...

. Black resigned because the position was a winning endgame for White (two knights and five pawns versus one knight and four pawns) . Petrosian won the match by one game to retain his title.

Kasparov vs. Shirov

In this 1994 game between World Champion Garry Kasparov
Garry Kasparov
Garry Kimovich Kasparov is a Russian chess grandmaster, a former World Chess Champion, writer, political activist, and one of the greatest chess players of all time....

 and Alexei Shirov
Alexei Shirov
Alexei Dmitrievich Shirov is a Soviet-born Latvian chess grandmaster. He has consistently ranked among the world's top players since the early 1990s, and reached a ranking as high as number four in 1998...

, White made an incredible sacrifice of a rook for a bishop (and no pawns): 17. Rxb7!!. As compensation for the sacrifice, Black became weak on the white squares, which were dominated by White's bishop. The exchange sacrifice also deprived Black of the bishop pair and his remaining bishop was a bad bishop. Black returned the exchange on move 28, making the material equal, but White had a strong initiative
Initiative (chess)
Initiative in a chess position belongs to the player who can make threats that cannot be ignored. He thus puts his opponent in the position of having to use his turns responding to threats rather than making his own. A player with the initiative will often seek to maneuver his pieces into more and...

. Black missed a better 28th move after which White could have forced a draw, but would have had no clear advantage. White won the game on move 38 .

Minor exchange

The minor exchange refers to the capture of the opponent's bishop
Bishop (chess)
A bishop is a piece in the board game of chess. Each player begins the game with two bishops. One starts between the king's knight and the king, the other between the queen's knight and the queen...

 for the player's knight
Knight (chess)
The knight is a piece in the game of chess, representing a knight . It is normally represented by a horse's head and neck. Each player starts with two knights, which begin on the row closest to the player, one square from the corner...

 (or, more recently, the stronger minor piece for the weaker) . Bobby Fischer
Bobby Fischer
Robert James "Bobby" Fischer was an American chess Grandmaster and the 11th World Chess Champion. He is widely considered one of the greatest chess players of all time. Fischer was also a best-selling chess author...

 used the term , but it is rarely used.

In most chess positions, a bishop is worth slightly more than a knight because of its longer range of movement. As a chess game progresses, pawn
Pawn (chess)
The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

s tend to get traded, removing support points from the knight and opening up lines for the bishop. This generally leads to the bishop's advantage increasing over time.

Traditional chess theory
Chess theory
The game of chess is commonly divided into three phases: the opening, middlegame, and endgame. As to each of these phases, especially the opening and endgame, there is a large body of theory as how the game should be played...

 espoused by masters such as Wilhelm Steinitz
Wilhelm Steinitz
Wilhelm Steinitz was an Austrian and then American chess player and the first undisputed world chess champion from 1886 to 1894. From the 1870s onwards, commentators have debated whether Steinitz was effectively the champion earlier...

 and Siegbert Tarrasch
Siegbert Tarrasch
Siegbert Tarrasch was one of the strongest chess players and most influential chess teachers of the late 19th century and early 20th century....

 puts more value on the bishop than the knight. The hypermodern
Hypermodernism (chess)
Hypermodernism is a school of chess that emerged after World War I. It featured challenges on the chess ideologies presented by central European masters, such as on Wilhelm Steinitz’ approach to the centre. It also challenged in particular the dogmatic rules set down by Siegbert Tarrasch...

 school favored the knight over the bishop. Modern theory is that it depends on the position, but that there are more positions where the bishop is better than where the knight is better .

There are some occasions when a knight can be worth more than a bishop, so this exchange is not necessarily made at every opportunity to do so.

A rook and bishop usually work better together than a rook and knight in the endgame , . José Raúl Capablanca
José Raúl Capablanca
José Raúl Capablanca y Graupera was a Cuban chess player who was world chess champion from 1921 to 1927. One of the greatest players of all time, he was renowned for his exceptional endgame skill and speed of play...

 stated that a queen and knight work better together than a queen and bishop in the endgame . More recently, John Watson
John L. Watson
John Leonard Watson is a chess International Master and author.Watson was born in Milwaukee and grew up in Omaha, Nebraska. He was educated at Brownell-Talbot, Harvard, and the University of California at San Diego, where he took his degree in engineering...

 has stated that from his study of this endgame that an unusually large proportion of queen and knight versus queen and bishop endings are drawn, and that most decisive games are characterized by the winning side having one or more obvious advantages (for example, having a knight against a bad bishop in a closed position, or having a bishop in a position with pawns on both sides of the board, particularly if the knight has no natural outpost
Outpost (chess)
An outpost is a square which is protected by a pawn and which cannot be attacked by an opponent's pawn. In the figure to the right, c4 is an outpost, occupied by White's knight...

). Watson states that positions in this endgame in general "are very volatile, and often the winning side is simply the one who starts out being able to win material or launch an attack on the opposing king" . Glenn Flear
Glenn Flear
Glenn Curtis Flear is a British chess grandmaster now living in Montpellier, France. He is the author of several books, some on chess openings and some on the endgame....

 agrees with that assessment for endgames. He could not find an endgame by Capablanca that supported his statement. The statistics for queen and bishop versus queen and knight endgames are about even. Most decisive games were won because of a significant advantage from the middlegame and only a limited number of positions show an inherent superiority for one over the other .

See also

  • Chess piece relative value
  • Chess terminology
    Chess terminology
    This page explains commonly used terms in chess in alphabetical order. Some of these have their own pages, like fork and pin. For a list of unorthodox chess pieces, see fairy chess piece; for a list of terms specific to chess problems, see chess problem terminology; for a list of chess related...

  • Chess strategy
  • Chess tactics
  • Chess theory
    Chess theory
    The game of chess is commonly divided into three phases: the opening, middlegame, and endgame. As to each of these phases, especially the opening and endgame, there is a large body of theory as how the game should be played...

  • Exchange (chess)
    Exchange (chess)
    In the tactics and strategy in the board game of chess, an exchange or trade of chess pieces is series of closely related moves, typically sequential, in which the two players capture each others pieces. Any types of pieces except the kings may possibly be exchanged, i. e. captured in an...


Further reading

  • Peter Wells
    Peter Wells (chess player)
    Peter Kenneth Wells is an English chess Grandmaster and author.Wells was British Rapidplay Chess Champion in 2002, 2003 and 2007.- External links :**...

    , "The Exchange Sacrifice Revisited – Part 1", ChessBase Magazine, #111, April 2006, pp. 18–24.
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