Two Bishops vs. Two Knights

Continuing with Smyslov's Sparklers, the interest in the current game stems from a battle of two Bishops vs. two Knights. In the diagrammed position Black played 19...Bxb2. Smyslov explained the move with the following:

Outwardly simple, but in actual fact a major decision. Euwe undoubtedly considered this reply, but hoped with the help of his two Bishops to win back the Pawn on b3 and obtain the better ending.So great is the conviction nowadays in the advantage of the two Bishops! Here it is interesting to recall that M.I.Chigorin readily carried on the struggle with two Knights and obtained repeated successes. In the art of chess there are no unalterable laws governing the struggle, which are appropriate to every position, otherwise chess would lose its attractiveness and eternal character.'

After 20.Rxb2 Rxa3 21.Kd2, Smyslov continued the train if thought:

Both players were aiming for this position: White has a strong center and two Bishops, but Black has an extra passed Pawn.The question is whether he can keep what he has won. The whole struggle, in which the Knights show great resourcefulness and activity, revolves around Black's passed Pawn. GM Keres suggests that the needs of the defense were most simply fulfilled by 21.Bd1 which does not allow Black to consolidate his Knight on c5. However, in the variation 21...Nc5 22.Bxc5 Rxc5 23.Rxb3 Rxb3 24.Bxb3 Rc1+ 25.Bd1 Nd7 Black preserves an indisputable advantage.'

Kasparov, who agreed with most of Smyslov's analysis, wrote, 'Although after 26.Kd2 Ra1 27.Kc3 and 28.Kb2 the most probable outcome is a draw.'

Moscow 1948 (Rd.24)
Smyslov, Vasily

Euwe, Max
(After 19.Nb5-a3)
[FEN "1nr3k1/1p1nppbp/6p1/3P4/r3P3/Np2BP2/1P2BP1P/1R2K2R b K - 0 19"]

The game continued 21...Na6 22.Rhb1 Nac5 23.Bd4. Smyslov:

It seems that it is not so easy to win back the Pawn. After 23.Bb5 Ne5 24.Bxc5 Rxc5 25.Rxb3 Nxf3+ 26.Ke3 Rxb5 27.Rxa3 Rxb1 28.Kxf3 f6 29.Rc3 h5 30.Rc7 Kf8, Black keeps his extra Pawn and with it his winning chances. • 23.Bd1 is now answered by 23...Ra2 24.Rxa2 bxa2 25.Ra1 Ra8 26.Kc3 e6 27.dxe6 fxe6 28.Bc2 b6 and if 29.Kb2, then 29...Ne5 and Black once again preserves his positional advantage.

A comment quoting Rybka analysis on Chessgames.com mentioned that 23.Bb5 Ne5 24.Be2 is better, but failed to give a plan. Indeed, it is not obvious how Black makes progress. Bringing the Black King to the Queenside looks best. At some point White will play Bxc5 Rxc5 followed by Rxb3 Rxb3, Rxb3 Rc7. This is similar to the analysis after 21.Bd1, where the Pawn count is equal, but Black has an outside passed Pawn that is difficult to convert.

Now Smyslov continued 23...e5, and gave himself a '!'. After 24.dxe6, he discredited Keres' analysis:

One should not reproach too severely for this exchange. Against 24.Be3 Black could continue 24...f5 25.exf5 gxf5 26.f4 exf4 27.Bxf4 Ra4 28.Be3 f4 (or 28.Bh6 Kf7). All Black's pieces are in play, while the White Rooks are tied up by the blockade of the enemy Pawn.

Keres recommends 24.Be3 as a satisfactory continuation for White, giving the variation 24...f5 25.exf5 gxf5 26.d6. Keres now asserts that "the White Bishops suddenly begin to show great activity". In fact after the simple 26...f4 27.Bc4+ Kg7 28.Bxc5 Nxc5 White has already had to part with his proud Black-squared Bishop. If 29.Bxb3 then 29...Rc6 wins the d-Pawn in return.

The move 24.Bc3 which the analysts have examined, also does not give White full equality. After 24...f5 25.exf5 gxf5 26.Bb5 26...b6 White must still labor under difficulties, and for all that Black preserves his extra Pawn. For example: 27.Bxd7 Nxd7 28.Rxb3 Rxb3 29.Rxb3 Rc5.

After 24...Nxe6 25.Be3 Ndc5 26.Bxc5, he criticized Keres' analysis again, starting:

So White gives up one of his Bishops and goes over completely to passive defense. The White Bishops did not show any superiority in the fight against the Knights, so it is understandable on psychological grounds that Euwe should decide on this exchange, which frees the square e3 for the King.

Euwe resigned on his 39th move. Why were the Bishops unable to show any advantage over the Knights. I would say because the fight occured on one side of the board only. In close quarter, hand-to-hand combat, Knights have certain advantages over Bishops. Only when the play ranges over the whole board do the Bishops' powers prove superior to the Knights'.

To play through the complete game see...

Max Euwe vs Vasily Smyslov, World Championship Match Tournament 1948
http://www.chessgames.com/perl/chessgame?gid=1042708

...on Chessgames.com.