The sacrifice of the exchange is often a way of trying to exploit special features in a position; in those cases the superficial material valuation of five points against three is meaningless. Of course the sacrifice of the exchange is even better for the side giving up the Rook if that side also gets one or more Pawns.
When deciding on whether or not to sacrifice the exchange masters rely mostly on calculation and the feel for the position rather than general considerations. However, here are a couple of rules of thumb that can be used as a guideline by the rest of us.
A) You can get an attack or a passed Pawn
B) Sacrifices that weaken the opponent’s P-structure or which lead
to a strong initiative will likely give winning chances.
When sacrificing the exchange it is wise to take the following generalizations into consideration:
A) With only a Pawn for the exchange the chances are it's an even exchange.
B) With just a R for N (no Ps) your opponent may be able to return the exchange and win a P himself.
C) If your opponent does not have a B, two Bs can sometimes equal
a R and N.
D) If the Ps are all on one side of the board, there is less danger of
losing the ending for the side that is down the exchange.
In the Sicilian Defense a black R often finds itself on c8 from where it puts pressure along the half-open file and so white, especially if he has castled Q-side, must always be on the lookout for a positional sacrifice of the exchange by black.
The ...Rxc3 exchange sacrifice is one of the most well known tactical patterns. This sacrifice can be used to serve several different purposes.
Actually, although it is most dangerous if white has castled Q-side, ...Rxc3 can be played regardless of which side white has castled on as it can be used for either immediate or long-term gains.
In positions where the players have castled on opposite sides it is likely to lead to very sharp positions. In this case both sides must balance their attack on the enemy K with the defense of their own. To do this requires experience, knowledge and intuition which is something we non-masters do not have to a great degree!
For the serious student who wants to gain knowledge of the exchange sacrifice studying a book such as The Exchange Sacrifice, A Practical Guide by Sergey Kasparov, a GM from Belarus, might be worthwhile. The nice thing about the book is the over 200 illustrative games.
Efim Geller is best remembered for his tactical ability and original attacking style which characterized his early career. In later years he became a more rounded player and an expert on openings.
He knew all about the ...Rxc3 sacrifice of the exchange in the Sicilian and we see him carry it off against Isaac Boleslavsky in their amazingly complicated game in the Zurich Candidates Tournament in 1953.
In his classic book on the tournament David Bronstein gave the impression that Geller had the game in hand from almost the beginning. Of course, with the benefit of engines we see that was not the case. In fact, the complications were so great that in going over this game I ran more Shootouts to get some idea of the results than I have in any game I have recently posted! As a reminder, Shootouts allow you to use one or more engines to play out the rest of the game at different ply depths with the sides being changed after each game.
Isaac Boleslavsky - Efim Geller
Result: 0-1
Site: Candidates Tmt, Zurich
Date: 1953
Sicilian Dragon: Yugoslav Attack
[...] 1.e4 c5 2.♘f3 ♘c6 3.d4 cxd4 4.♘xd4 ♘f6 5.♘c3 d6 6.g3 ♗g4 An interesting move that forces Geller to play 7.f3. The opening ends up with Boleslavsky playing the Rauzer Attack against Geller's Dragon. 7.f3 ♗d7 8.♗e3 g6 9.♕d2 ♗g7 10.O-O-O O-O 11.g4 ♖c8 12.♔b1 ♘e5 13.h4 Let's let Bronstein explain this position! White has a well placed N on d4; from there it can meet black's counterattacking ...Qa5 with Nb3 which force the Q to retreat. Additionally, white has started his P-storm first, having already played g3-g4 and h2-h4. Note that the position of white's K has no weakness while black's P on g6 is a focal point for white's advancing Ps. For his part, although black will be starting his P advance later than white, black already has open against white's K. Also, his centralized N t is very well placed as it attacks the weak link in white's P-chain, the P on f3 which is the only support of white's whole shaky P-chain. Black controls, and may soon occupy, the important square c4. Meanwhile, white still does not control one square in the immediate area of black's K. Finally, the powerful B on g7 may give rise to dangerous tactics on the long diagonal. All of this adds up to a position that is in a state of dynamic equality and great skill is necessary in order to maneuver the entire mass of Ps and pieces while simultaneously countering the enemy's operations. 13...b5 This prepares both ... b4 and ...Nc4. After ...Nc4 white must avoid Bxc4 because black would recapture, not with the R, but with the P because th e semi-open b-file would be more dangerous for white than the semi-open c-file. 14.♗h6 Taking the b-pawn would be madness, of course. And h4-h5 is ineffective so long as Black's pieces solidly defend the squares h7 and h8; so first white wants to trade off one of the most important defensive pieces.
14.♘cxb5 is not advisable. 14...♘xf3 15.♘xf3 ♘xe4 16.♕g2 ♗xb2 17.♔xb2 ♗xb5 18.♗xb5 ♕a5 19.c4 (19.♗d3 ♖b8+ mates in 3.) 19...♕c3+ 20.♔b1 ♕xe3 This position is very complicated and five Shootouts were all drawn. However, it required very careful defense on white's part to hold the draw and in practice the slightest slip would be disastrous.
14...♗xh6
14...♗h8 trying to use the B on the long diagonal fails. Jst a sample of what could happen... 15.♗xf8 ♔xf8 16.h5 g5 17.♕xg5 ♖xc3 18.bxc3 ♘xf3 19.♘xf3 ♘xe4 20.♕f4 ♗c6 21.♘g5 ♘xg5 22.♕xg5 ♗xh1 23.♗d3 ♗f6 24.♕xb5 ♗f3 25.♖f1 ♗xg4 26.h6 White has a won ending and won 5 Shootouts. Here is the rest of the game at 17 plies. 26...♗d7 27.♕b7 ♗xc3 28.♗xh7 e6 29.♗g6 f5 30.♕b3 ♕f6 31.h7 ♕xg6 32.♕xc3 ♕xh7 33.♕f6+ ♕f7 34.♕d4 ♕g7 35.♕xd6+ ♕e7 36.♕e5 ♕g7 37.♕e3 a5 38.♖g1 ♕f6 39.♕a3+ ♔f7 40.♕h3 ♔e7 41.♕h7+ ♔d8 42.♖d1 ♕e7 43.♕h8+ ♔c7 44.♕e5+ ♔b6 45.♕d4+ ♔b5 46.♕xd7+ ♕xd7 47.♖xd7
14...b4 is met by 15.♘d5 ♘xd5 16.exd5 ♗xh6 17.♕xh6 and white's attack will come first.
14...♘c4 15.♗xc4 bxc4 16.♗xg7 ♔xg7 17.h5 Here, too, white's attack comes first.
14...♖xc3 is also unsatisfactory. 15.♗xg7 ♖xf3 16.♗xf8 ♕xf8 17.♘xf3 ♘xf3 18.♕e3 ♘e5 19.g5 ♘xe4 20.h5 (20.♕xe4 ♗c6) 20...♘c5 21.hxg6 ♘xg6 22.♗h3 ♗c6 White, being the double exchange ahead, is winning. Here is how Stockfish accomplished it. 23.♖h2 ♗e4 24.♗g2 ♗xg2 25.♖xg2 ♕c8 26.♖h1 ♕e6 27.♕f3 ♕e4 28.♕h3 ♘f8 29.♖f2 ♕e6 30.g6 fxg6 31.♕f3 ♘cd7 32.♖hf1 ♘f6 33.♖e2 ♕d7 34.♖fe1 ♔f7 35.♖xe7+ ♕xe7 36.♖xe7+ ♔xe7 37.♕b7+ ♘8d7 38.♕xb5 h5 39.♕g5 ♔f7 40.a4 ♘e5 41.♕e3 ♘c6 42.♕b3+ ♔e7 43.♕b7+ ♔d8 44.♕xc6 ♘e8 45.♕a8+ ♔d7 46.♕xa7+
15.♕xh6 ♖xc3 h4-h5 was a real threat now, so this exchange of rook for knight, which also breaks up the king's cover, was practically forced. 16.bxc3 ♕a5 The natural attacking continuation. 17.♕e3 White's king position is loosening, and his queen must now return to the defense. On the other hand, the position is still in balance, since White has the exchange as compensation. 17...♕a3 Another interesting position, especially these days with engines at our disposal. In annotating this game in his great book on the Zurich tournament, Bronstein makes no comment on the next couple of moves, but Stockfish is critical of them. In fact, many of Bronstein's remaining comments are erroneous, but let's not be too critical because he did not have Stockfish and Komodo. If anything, his comments and the engine's analysis show the complexity of the rest of the game!
17...♖c8 Has been tried in later games. 18.♔b2 Less precise is 18. Nb3 18...b4 19.cxb4 ♕xb4+ 20.♕b3 ♕c5 21.♗a6 and white soon won. Escandell Mari, J (2158)-Sauleda Roig,J (2172)/ Barcelona 2005
17...♘c4 This is totally unsatisfactory. 18.♗xc4 bxc4 19.h5 ♖b8+ 20.♔a1 e5 21.♘e2 ♖b6 22.♖b1 ♖a6 23.♖b2 and white has a winning position.
18.h5 Bronstein appears to have based his annotations to a large extent on the results. In auto-annotation mode this move gets two ? from the engines which swing the evaluation to black's favor after this move. In order to maintain a slight advantage white had to take a moment to make some defensive moves.
18.♗e2 ♖c8 19.♕c1 ♕xc3 and now 20.h5 with the better position, but only slightly!
18...b4 Logical, but the players and Bronstein missed a tactical shot that secures the advantage.
18...♘xf3 19.♕xf3 ♗xg4 20.♕e3 ♗xd1 Black has won back the exchange and is even a couple of Ps ahead. Besides that he has an adequate defense for his K.
18...♖c8 was a less good alternative for black. 19.♘b3 a5 20.♗e2 b4 21.cxb4 a4 22.b5 axb3 23.cxb3 ♗e6 24.♖c1 ♖a8 25.♖c2 In the long run white's position will prove superior.
19.♕c1 If black is to have any hopes of attacking he cannot exchange Qs. 19...♕xc3
19...♕xc1+ 20.♖xc1 bxc3 21.♔a1 ♖b8 22.♖b1 ♖xb1+ 23.♔xb1 and white should prevail.
20.♕b2 Even better was the march of the Ps starting with 20.h6
20.h6 a5 21.g5 ♘h5 (21...♘e8 22.♕d2 ♕c7 23.f4 and black's forces are beaten back.) 22.f4 ♘g4 23.♗h3 f5 24.exf5
20...♖c8 Bronstein comments: Black refrains from 20... Qe3, which could result in a repetition of moves. Black has no advantage and after the exchange of Qs his game becomes perhaps even a bit inferior. Bronstein's comment is correct, but what he failed to notice is that with 20... Nxf3 black fully equalizes.
20...♘xf3 21.♕xc3 (21.hxg6 ♘d2+ 22.♔c1 ♘fxe4 23.gxh7+ ♔h8 24.♗d3 ♘f2 is also equal.) 21...bxc3 22.♘xf3 ♗xg4 This same idea was seen in the note to black's 18th move.
21.hxg6 This more or less forces black to trade Qs and it should be nted that at this point it is white who stands slightly better. 21...♕xb2+ (21...fxg6 22.♕b3+ ♔g7 23.g5 is also unpleasant for black.) 22.♔xb2 hxg6 23.a3 Bronstein comments that this is an inaccuracy of such magnitude that it loses the game, but that is more fiction than fact. True, it is an inaccuracy, but all it does is let his position slip from better to equal.
23.g5 keeps white slightly better after 23...♘h5 24.♖h4 a5 25.f4
23...bxa3+ 24.♔xa3 Bronstein recommended 24.Ka2, but Boleslavsky played this based on a miscalculation. Even so, there is nothing wrong with the move played. 24...♘xf3 Boleslavsky saw this. 25.♘xf3 ♖c3+ When he played 24.Kxa3 Boleslavsky envisaged that he could meet this with 26. Rd3 guarding the N! Still, the position is equal. 26.♔b2 ♖xf3 27.e5 It is here that Boleslavsky starts to go astray.
27.g5 is the correct move. 27...♘xe4 28.♗g2 ♘xg5 29.♗xf3 ♘xf3 30.♖a1 ♗f5 31.♖xa7 with an incredibly unbalanced position. Five Shootout games were drawn.
27...♘xg4 With this move white's position cracks. 28.♗e2 ♖f2 29.♗xg4 ♗xg4 30.♖df1 But, this is the move that loses the game.
30.♖d4 would have allowed black to play on. 30...♗f5 31.exd6 ♖xc2+ 32.♔b3 exd6 33.♖xd6 Black is slightly better, but it's time for another Shootout! Black won one game and 4 were drawn.
30...♖xf1 31.♖xf1 dxe5 As Bronstein correctly pointed out, no R can fight a B and four Ps!. 32.c4 ♔f8 33.♖a1 Going after the a-Pawn costs time which black will use to advance his horde of Ps on the K-side.
33.c5 would not have saved the game though. 33...♔e8 34.c6 f5 35.c7 ♔d7 36.♖c1 ♔c8 37.♖c6 f4 38.♖xg6 ♗f5 39.♖g5 e6 and wins.
33...♗f3 34.c5 g5 35.♖xa7 g4 36.♖a3 ♔e8 37.♔c1 f5 38.♔d2 f4 39.♖a6 g3 40.♔e1 ♗e4 One assumes the time control has been reached and so white resigned. An extraordinarily complicated game! Powered by Aquarium
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