Beat The ... Trompowsky

IN this series I am looking at the statistically best way to play against popular opening lines.

The numbers are drawn from the 2021 edition of ChessBase's Mega database, ignoring, where possible, those results that include very few games and so are statistically insignificant.

The Trompowsky: 1.d4 Nf6 2.Bg5 goes through surges of popularity, often based on the publication of a dedicated book or repertoire recommendation.

Black's most-popular reply is 2...Ne4, which scores a respectable 46%.

But the most-successful move is Nakamura's favourite, 2...c5, which scores an excellent 50%.

Position after 2...c5

White has four main tries.

A) 3.Bxf6 (3,430 games)

The thematic move of the Trompowsky, but it only scores 49%, so Black already has an edge, statistically speaking.

Capturing towards the centre with 3...gxf6 is normal, at which point White usually pushes on with 4.d5 and Black replies 4...Qb6.

White could defend with 5.b3, but scores just 38%, so the main move is the ugly-looking 5.Qc1.

Black has a big choice here, but the most successful of the statistically significant ones is 5...d6, scoring 51%.

This is about as far as we can get with reasonable sample sizes. The position is rated as equal by the analysis engines Stockfish13 and Komodo12.1.1.

B) 3.d5 (2,411 games)

White grabs space, but gives Black a second chance to avoid the thematic capture on f6, and this, from a statistical view, is what Black should do by playing 3...Ne4, which scores 51%.

White usually replies 4.Bf4 (the other natural-looking retreat, 4.Bh4, scores an abysmal 15%, albeit from a small sample), when again it is time for 4...Qb6.

White has three popular continuations.

B1 5.Bc1, when 5...e6 6.f3 Nf6 7.e4 scores 51% for Black, while Kasparov's choice of 7.c4 is slightly less popular and scores 53% for Black.

B2 5.Nd2!? Qxb2 6.Nxe4 Qb4+ 7.Qd2 Qxe4 scores 54% for Black.

B3 5.Qc1 again looks ugly and is well-met by 5...c4 6.e3 Qa5+ 7.Nd2 c3! 8.bxc3 Nxc3, which scores 59% for Black.

C) 3.Nc3 (845 games)

This simple developing move is best met statistically by 3...d5, which scores 49%.

White has two main replies.

C1 4.Bxf6 gxf6, when this line splits:

C1.1 5.e3, after which Black scores 59% with 5...Nc6, rising to 61% after 6.Qh5 cxd4 7.exd4 e6.

C1.2 5.e4!?, after which Black scores 57% with 5...exd4, rising to 65% after 6.dxc5 f5 7.Qxd8+ Kxd8 8.0-0-0+ Bd7.

C2 4.e3. when 4...cxd4 scores a tremendous 72%, rising to 81% after 5.exd4 Nc6 and to 77% after 5.Qxd4 Nc6.

D) 3.dxc5 (304 games)

Black scores 58% with the unusual 3...Na6!?

The main line runs 4.Nc3 Nxc5 5.Bxf6 gxf6, after which Black scores a still very good 55%.