Davidson - Alekhine, Semmering 1926

Of all the games in this series on Alekhine's annotated brilliancies, this is the game I've least understood. White plays a small inaccuracy in the opening, which Alekhine exploits to force a slight weakening of the Kingside. Then he forces White's Bishops onto awkward squares. This allows him to threaten exchanges, including a Queen exchange, which White must decline to avoid a severe positional advantage. Instead of losing slowly in a positional game, White goes down in a vicious Kingside attack.

My first problem was what position to use as a starting point. The opening inaccuracy doesn't explain the later difficulties. The little tactical tricks that force the Kingside weakening are interesting, but they also don't explain the loss. Finally I decided to use the exchange offers that seek a positional concession. Note that Black's last move appears to undevelop his game and to block the Bc8.

Semmering 1926
Alekhine, Alexander

Davidson, Jacques
(After 18...Nb6-d7)
[FEN "r1b1r1k1/ppbnqp1p/2p3p1/7n/3NP3/3BB2P/PPQ1NPP1/R3R1K1 w - - 0 19"]

White continued 19.Nf3, and Alekhine noted,

After this retreat Black gets a definite pull. I expected here 19.f4 Ndf6 20.e5 Nd5 21.Bd2 Bb6 after which, although Black's game would still remain preferable, White would not be without some fighting chances.

19...Bb6! Alekhine:

Expecting to increase the positional advantage already obtained -- after 20.Bxb6 axb6 -- on account of the open a-file. In order to avoid this unpleasant variation White tries with his next two moves to complicate matters, but only succeeds in accelerating the catastrophe.

20.Bg5 Qc5! 21.Nc3 Alekhine:

If now 21.Qxc5 Nxc5 22.Nc1 (forced) 22...f6 23.Bd2 Nxd3 24.Nxd3 Ng3 25.e5 Bf5 with a winning positional advantage.

21...Ne5! Alekhine:

Forcing the following exchange and thus renewing the attack on the b8-h2 diagonal, which will prove decisive.

22.Nxe5 Qxe5 23.Be3 Bc7 24.Ne2 (24.g3 Bxh3) 24...Qh2+ 25.Kf1 Bxh3!. Now Black won by sacrificing the minor pieces to strip the White King of Pawn cover, and the major pieces delivered the knockout.

This is all excellent play, but it raises some questions. Is the diagrammed position lost? If so, how could White have improved previous play? If not, how could White have saved the game. There are at least three possibilities: (1) Alekhine's suggestion of 19.f4; (2) 20.Bxb6; (3) The variation that starts 21.Qxc5 and leads to a 'winning positional advantage'. Can White save his game tactically with 26.Bf4 Ne4 or 26...Nh5?

To play through the complete game see...

Jacques Davidson vs Alexander Alekhine, Semmering 1926
http://www.chessgames.com/perl/chessgame?gid=1007549

...on Chessgames.com.