I was struck recently when discussing this position with the coaching group:
White's next move, 15. Nh4 , was regarded with scorn by some - " he's just playing for a draw ". On the contrary, provoking the exchange of Queens looked like a reasonable winning attempt to me! In fact, Black did swap with 15...Qxg4 without much thought about alternatives, when 15...Qe6 might have been worth a look.
Some players seek exchanges and some avoid them; I get the impression that juniors exchange without much hesitation.
Exchanges are just moves, says Stephen Gerzadowicz. They have good and bad effects, and are better for one side or another. Weight these up, then decide whether to exchange or not. Fortunately, there are some general guidelines to help us.
Rules for exchanging
- If you are ahead in material, exchange pieces (but not Pawns)
- If you are behind in material, exchange Pawns (but not pieces)
- Avoid the exchange of your most active piece (especially if you are defending)
- If you have more space, are attacking the King, or have Pawn weaknesses, avoid exchanges (especially of Queens).
- If you have less space, are defending the King, or have better Pawn structure, seek exchanges (especially of Queens).
- If you have the advantage of the two Bishops, avoid the exchange of your opponent's remaining Bishop for one of your Bishops.
- If you have two Rooks and your opponent only one, seek the exchange of your opponent's remaining Rook for one of your Rooks.
- Avoid being left with a permanently poor piece, like a Bad Bishop
- Last but not least, look at the effect of the exchange on the position. Have you improved the opponent's Pawn structure? Have you brought into play an opposing piece?
Having looked at all these ideas, we can perhaps understand the position given more clearly. The Black Bishop is poor but not yet Bad; Black has the worse Pawn structure, and the Queen is one of his most active pieces. The exchange draws the h-Pawn in to become a g-Pawn, so White can play g3 and f4 without fearing that ...exf4 will split his Pawns. Also, White is GM David Norwood, who might have thought that a technical endgame might expose his amateur opponent's deficiencies.
Okay, let's look at these guidelines in examples.
If you are ahead in material, exchange pieces (but not Pawns)
If you are behind in material, exchange Pawns (but not pieces)
Right
Regis,D - Walker,J [C33] Exeter vs. Teignmouth, 1994
34.b6 ! 34...axb6 35.Rxb6+ Kg5 36.Rb5+ Kg6 37.Rc5 h6 38.Rb5 f6 39.Rc5 Re3 40.Rc7 Re5 41.Kg3 h5 42.Rc3 hxg4 ? 43.hxg4 Kg5 44.Ra3 g6 45.Rb3 Re4 46.Rb5+ f5 ? [46...Re5 47.Rb4] 47.gxf5 gxf5 48.Rb8 Re3+ 49.Kf2 Ra3 50.Rb4 f4 51.Rb8 1/2../strong>
the basic draw: Philidor's position White has been steering for this since move 33!
Wrong
Hecht,H - Spassky B V [B31] Dortmund, 1973
Black should retain the Rook by 50...Rc5.
50...Rxe1 51.Kxe1 Ke7 52.Kd2 Kd6 53.Kd3 Ke5 54.a5 a6 55.b4 Kd5 56.Kc3 gxh4 57.gxh4 Ke5 58.Kc4 Kd6 59.b5 axb5+ 60.Nxb5+ Ke5 61.Kc5 Bc8 62.Kb6 Bstrong 63.a6 Bg2 64.f4+ Kxf4 65.Nd6 f5 66.Nb7 Kg3 67.a7 f4 68.a8Q f3 69.Qb8+ 1-0
Avoid the exchange of your most active pieces (especially if you are defending)
Wrong
van Scheltinga - de Groot [E94] errors: eagerness to exchange, 1936
1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5 7.0-0 Nfd7 8.Be3 Nc6 9.Qd2
9...exd4 10.Nxd4 Nxd4 11.Bxd4 Bxd4 12.Qxd4 Qf6 13.Qd2
The exchanges have left White dominating the board.
13...Qe5 14.f4 Qc5+ 15.Kh1 Nf6 16.b4 Qxb4 17.Qd4 Kg7 18.Nd5 Qc5 19.Qxf6+ 1-0
I couldn't find another example of this from the point of view of exchanges, but if you think about retreating as having the same effect:
Nimzowitsch,A - Capablanca,J [C62] St Petersburg (1), 1914
1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6 4.Bb5 d6 5.d4 Bd7 6.Bxc6 Bxc6 7.Qd3 exd4 8.Nxd4 g6 9.Nxc6 bxc6 10.Qa6 Qd7 11.Qb7 Rc8 12.Qxa7 Bg7 13.0-0 0-0 14.Qa6
White has grabbed a Pawn on the Queen's-side. It is striking how quickly White's game deteriorates:
14...Rfe8 15.Qd3 Qe6 16.f3 Nd7 17.Bd2 Ne5 18.Qe2 Nc4 19.Rab1 Ra8 20.a4 Nxd2 21.Qxd2 Qc4 22.Rfd1 Reb8 23.Qe3 Rb4 24.Qg5 Bd4+ 25.Kh1 Rab8 26.Rxd4 Qxd4 27.Rd1 Qc4 28.h4 Rxb2 29.Qd2 Qc5 30.Re1 Qh5 31.Ra1 Qxh4+ 32.Kg1 Qh5 33.a5 Ra8 34.a6 Qc5+ 35.Kh1 Qc4 36.a7 Qc5 37.e5 Qxe5 38.Ra4 Qh5+ 39.Kg1 Qc5+ 40.Kh2 d5 41.Rh4 Rxa7 0-1
Znosko-Borovsky says, " A player who is at disadvantage in time should keep up any available threat" . That is, the Queen was better on a6, restricting the freedom of action of Black's pieces.
If you have more space, are attacking the King, or have Pawn weaknesses, avoid exchanges (especially of Queens).
Right
Timman,J - Petrosian,T, Las Palmas izt (2), 1982
1.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.Nc3 c6 5.a4 Bg4 6.Ne5 Bh5 7.f3 Nfd7 8.Nxc4 e5 9.Nxe5 Nxe5 10.dxe5 Nd7 11.f4 Bb4 12.Qc2 Qe7 13.e4 g5 14.Be2 gxf4 15.e6 Qh4+ 16.Kf1 Bxe2+ 17.Qxe2 fxe6 18.Qf2
18...Qe7 19.e5?! Nxe5 20.Bxf4 Rf8 21.Rd1 Bc5 0-1
White's elaborate Bishop manoeuvres in the main line Ruy Lopez are at least in part designed to keep Black burdened with a full complement of minor pieces.
Kasparov,G (2800) - Karpov,A (2730) [C92](W (20), 1990
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.0-0 Be7 6.Re1 b5 7.Bb3 d6 8.c3 0-0 9.strong Bb7 10.d4 Re8 11.Nbd2 Bf8 12.a4 h6 13.Bc2 1-0
This was crowned by a famous attack.
14.cxd4 Nb4 15.Bb1 c5 16.d5 Nd7 17.Ra3 f5 18.Rae3 Nf6 19.Nh2 Kh8 20.b3 bxa4 21.bxa4 c4 22.Bb2 fxe4 23.Nxe4 Nfxd5 24.Rg3 Re6 25.Ng4 Qe8 26.Nxh6 c3 27.Nf5 cxb2 28.Qg4 Bc8 29.Qh4+ Rh6 30.Nxh6 gxh6 31.Kh2 Qe5 32.Ng5 Qf6 33.Re8 Bf5 34.Qxh6+
[34.Nf7+ Matt/Mate in 6! 34...Qxf7 35.Qxh6+ Bh7 36.Rxa8 Ne7 37.Rxf8+ Ng8 38.Rgxg8+ Qxg8 39.Qxh7#]
34...Qxh6 35.Nf7+ Kh7 36.Bxf5+ Qg6 37.Bxg6+ Kg7 38.Rxa8 Be7 39.Rb8 a5 40.Be4+ Kxf7 41.Bxd5+ 1-0
Wrong
Kortchnoi,V (2695) - Karpov,A (2700) [D31], 1981 [Wcstrong0-Merano (9)]
16. Ne4?
Undoubtedly a mistake, freeing Black's game. As we can see from the sequel, though, White was trying to win, not merely play the best moves.
16...Nxe4 17.Qxe4 Bc6 18.Nxc6 Rxc6 19.Rc3?!
[19.Rxc6 Nxc6 20.d5 exchanges the IQP leaving nothing much left to play for.]
Black won the endgame.
If you have less space, are defending the King, or have better Pawn structure, seek exchanges (especially of Queens).
Right
1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Bg5 Be7 5.e3 0-0 6.Nf3 Nbd7 7.Rc1 c6 8.Bd3
Capablanca's freeing manoeuvre took most of the sting out of the QGD:
8...dxc4 9.Bxc4 Nd5 10.Bxe7 Qxe7 11.0-0 Nxc3 12.Rxc3 e5 13.dxe5 Nxe5 14.Nxe5 Qxe5 =
You will see Capa play like this in many games.
Wrong
Littlewood,P - Mestel,J [E61] Hastings (9), 1981
1.d4 Nf6 2.Nf3 g6 3.c4 Bg7 4.Nc3 0-0 5.e4 c6 6.e5 Ne8 7.Bf4 d6 8.strong Nd7 9.exd6 Nxd6 10.Be2 Re8 11.Qd2 Nf5 12.Rd1 c5 13.Nb5 Nf8
The simple 14. dxc5 wins a Pawn and seeks exchanges. Instead White wins an exchange, but allows counterplay.
14.Nc7 Nxd4 15.Nxe8 Qxe8 16.Ne5 f6 17.Nd3 b6 18.0-0 Bb7 19.Be3 e5 20.Rfe1 Rd8 21.Bxd4 Rxd4 22.Bf1 Ne6 23.f3 h5 24.b4 cxb4 25.Qxb4 Bf8 26.Qc3 Qd7 27.Kh1 Kh7 28.Qc2 Bc6 29.Qb1 Ba4 30.Rd2 Bh6 31.Rb2 Bf8 32.Nf2 Ba3 33.Ne4 Kg7 34.Rf2 Bc6 35.Nc3 Bc5 36.Nb5 Rh4 37.Rd1 Nd4 38.Nxd4 Rxd4 39.Re1 Rh4 40.Rd1 Rd4 41.Re1 h4 42.Rb2 Qd6 43.Rb3 e4 44.fxe4 Qe5 45.Rbe3 Bd6 46.g3 Rxe4 47.Qxe4 Bxe4+ 48.Rxe4 Qxg3 49.R4e2 Bb4 50.Rd1 Qf3+ 51.Kh2 Bd6+ 52.Kg1 Bc5+ 53.Kh2 Qg3+ 54.Kh1 Qg1# 0-1
If you have the advantage of the two Bishops, avoid the exchange of your opponent's remaining Bishop for one of your Bishops.
Right
Wrong
If you have two Rooks and your opponent only one, seek the exchange of your opponent's remaining Rook for one of your Rooks.
Right
Wrong
Avoid being left with a permanently poor piece, like a Bad Bishop
Right
Bryson,D - Williams,C [C12] BCCC, 1984 [TDH]
18...Bb5
The classic French manoeuvre to offload the bad Bishop.
Wrong
Booth,C (1800) - Regis,D (1825) [A42] Exeter vs. Harrogate, National Major Plate Final, 1996
Black has been left with classic KID bad Bishop.
22.b4 b6 23.a4 a5 [23...Bh4 24.a5] 24.Rxg8 Kxg8 25.bxa5 bxa5 26.Rb1 h5 27.Ke3 Bh4 28.Rb5 Rf4 29.Rxa5 Bxf2+ 30.Nxf2 Rxc4 31.Ne4 h4 32.Nd2 Rc3+ 33.Ke4 Kf7 34.Ra7 Kf6 35.a5 c6 [35...] 36.dxc6 Ke6 37.Rd7 Rxc6 38.Rd8 Rc3 39.Re8+ Kf7 40.Rh8 Ra3 [40...] 41.Nc4 Ra4 42.Kd5 Ra1 43.Rxh4 Rd1+ 44.Kc6 e4 45.Nxd6+ 1-0
Last but not least, look at the effect of the exchange on the position. Have you improved the opponent's Pawn structure? Have you brought into play an opposing piece?
Right
Forintos,G - Gligoric,S [E77] Ljubljana, 1969
1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.f4 0-0 6.Be2 c5 7.d5 e6 8.Nf3 exd5 9.exd5
9...Nh5 (Spassky) 10.0-0 Bxc3 11.bxc3 f5 12.Ng5 Ng7
A wonderful transformation, despite the loss of the Bg7 which is so often the salvation of Black's game. White's Pawns are blockaded across the board, and Black's weak e6 square is comfortably under observation.
13.Bf3 Nd7 14.Re1 Nf6 15.Rb1 Re8 16.Rxe8+ Qxe8 17.Rb2 Bd7 18.Rxb7 Rb8 19.Rxb8 Qxb8 20.Qc2 h6 21.Nstrong Qe8 22.Bd2 Ba4 23.Qc1 Ng4 24.Nf2 Nxf2 25.Kxf2 Qe7 26.Kg1 Ne8 27.Qb1 1/2../strong>
Wrong
How often do we see in club play, ...Bg4, ... Bxf3, then Qxf3 or Nxf3 when the net effect is that Black has lost the Bishop pair and brought out a White piece. Here's a more complex example:
Peters, J - Andersson,U [B15] defence: mending weaknesses, 1978
1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nf6 5.Nxf6+ exf6 6.Bc4
White's Queen's-side majority is a big engame plus, so White was startled by...
6...Qe7+ 7.Qe2 Be6
Black will only enter an endgame on certain conditions!
8.Bxe6
[8.Bb3 is the only testing continuation]
8...Qxe6 9.Bf4 Na6
The threat of ...Nb4 eventually prompts the exchange on e6
10.0-0-0 0-0-0 11.Qxe6+ fxe6
White has drifted into a dull position.
12.h4 c5 13.Be3 cxd4 14.Bxd4 Bc5 15.Ne2 e5 16.Bxc5 Nxc5
Black has no problems and even won.
Further Reading
TAULBUT & JONES, Chess Exchanges (Pergamon)
MEDNIS From the Middlegame to the Endgame (Cadogan)
EUWE & KRAMER The Middle Game, Vol. II - Chapters on Liquidation (Bell).
Capablanca was the great artist of exchanges, in defence and attack.