There are many ways to create an imbalance in chess. For example you can alter the pawn structure, obtain the bishop pair, castle on opposite sides. But the most obvious way is to sacrifice material. Gambits usually involve sacrificing a pawn for the initiative or some positional gain. Sacrificing a whole piece is more spectacular and generally relies on a short-term tactical justification where you might recover the material with interest or even deliver checkmate.

The exchange sacrifice is in a category of its own. You give up a rook for your opponent’s bishop or knight. Sometimes you get a pawn for it, sometimes you don’t. You’re looking for an enduring positional advantage based on superior piece activity. The classic example is in the Sicilian where Black sacrifices his rook for the white knight on c3, wrecking his opponent’s pawn structure and sometimes picking up the e4 pawn as well. Here’s Kasparov showing how to do it, on the black side of a Sicilian Najdorf against Movsesian in a tournament in Sarajevo in 2000.

13…Rxc3! 14.bxc3 Qc7
What has Kasparov got in return for sacricing the exchange? No extra material, but White’s queenside pawns are wrecked and Black’s minor pieces are ready to join the attack.
15.Ne2 Be7 16.g5 0-0 17.h4 Na4 18.Bc1 Ne5 19.h5 d5 20.Qh2 Bd6 21.Qh3
Both sides are attacking on opposite wings, but Black’s pieces are much more active and co-ordinated and his attack is much more dangerous.
21…Nxd3 22.cxd3 b4 23.cxb4 Rc8 24.Ka1?!
This gives Kasparov the opportunity to detonate the centre, when his pieces swim like sharks towards the defenceless white king.
24…dxe4 25.fxe4 Bxe4!
White can’t take the bishop: 26.dxe4 Be5+ and mate follows shortly.
26.g6 Bxh1 27.Qxh1 Bxb4 28.gxf7+ Kf8 29.Qg2 Rb8 30.Bb2 Nxb2 31.Nd4 Nxd1 32.Nxe6+ Kxf7 0–1
White’s knight forks king and queen, but he can’t take the queen because it’s mate in one.

Actually this is just the most famous kind of exchange sacrifice. There are many different ways to do it. Their sheer variety is one of the themes to emerge from a new book by Kotronias entitled ‘The Exchange Sacrifice according to Tigran Petrosian’. Kotronias argues that the former Soviet-Armenian world champion was the greatest exponent of the exchange sacrifice. The book brings together many examples from his games, usually successful but sometimes not, and all annotated in detail. This is from the game Troianescu–Petrosian, Bucharest 1953, in which Petrosian manages to sacrifice the exchange not once, but twice.

25…Rxe4! 26.Bxe4 Bxe4
This time Black gets a pawn for the exchange. His central pawn majority and active pieces provide more than enough compensation.
27.Nc2 d5 28.Nd4 b4 29.cxb4 axb4 30.a4 Qa7 31.Qf2 Rc8 32.b3 Bf8 33.Nb5 Qa6 34.Qe2 Qb6+ 35.Kf1

35…Rc3
Here we go again… but this time Petrosian is grandstanding. He probably couldn’t resist giving up a second rook, but a better plan is 35…h5 intending to advance to h4, open the h-file, and bring a rook to the side with a very dangerous attack.
36.Nxc3?
Taking the material, so that temporarily White has two rooks for two bishops, but it soon becomes clear that the bishops are the stronger pieces.
36…bxc3 37.Rc2 Qxb3 38.Rec1 Bb4 29.g4 Bxc2 30.Rxc2 Qxa4
That’s one exchange back, with a lot of extra pawns. White can do nothing about this. Petrosian gradually advanced his pawns and White resigned on move 57.

The exchange sacrifice is part of the strategic arsenal of every strong player. What interests me is that this form of material disdain has crossed the boundary to computer chess. Traditionally the engines would prefer to take material and hang on to it. But now they know that material gain is not everything. They are prepared to sacrifice for long-term gain in the greater interest. The final example in today’s post is from another correspondence game. Jean-Paul Dellenbach (2079) v Rodney Barking, ICCF 2022.

White has just played 23.Bh6, attacking the rook and no doubt expecting it to move. But, on advice from the computer, I left the rook where it was.
23…dxe4 24.Bxf8 Rxf8 25.dxe4
I didn’t get any pawns back. But the computer has worked out that White is now very weak on the dark squares and will have trouble defending them given than his pieces are passively placed.
25…Bc7 26.Bc2 Qd6 27.g3 Re8 28.Kh2 Re5
Bringing the last piece into the attack. The rook is destined for the h-file where it will bear down directly on the white king. I’m not sure I would have thought of this manoeuvre unaided.
29.Qf2 Qe7 30.Nf4 Nxf4 31.gxf4 Rh5 32.Qe3 Bc8 33.Rf3 g5!
Exploiting the pin on the f4-pawn to open the position further.
34.e5 gxf4 35.Rbxf4 Qxe5
White decides to return the exchange, but this doesn’t stop the attack.
36.Kg2 Bxh3+ 37.Rxh3 Qxe3 38.Rxe3 Bxf4 39.Rh3
The smoke has cleared and White is now two pawns down. His best hope is to get the rooks off the board and reach an opposite bishop ending with drawing chances despite the material deficit. I didn’t need a computer to tell me that rook and opposite bishop endings are anything but drawish, so it was an easy decision to keep the rooks on even though White now gets one of his pawns back.
39…Rc5 40.Bxh7+ Kg7 41.Bd3 Be5 42.Rh7+ Kf8 43.Rh6 f6 44.Rh7 Rxc3 45.Bxb5 Rc2+ 46.Kf3 Rxa2 47.Ra7 a3
Two safe pawns up again, with rooks and bishops still on the board, Black is winning this ending. White could have prolonged the struggle but blundered on move 53 and resigned.