Beat The ... Nimzo-Indian

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 Nimzo-Indian: 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 is one of the very most-popular responses to 1.d4.

White's most-successful continuation statistically is 4.g3!?, scoring 54%.

It has the practical advantage of being just the eighth most-popular continuation, so it is unlikely many blacks will be well-prepared.

Position after 4.g3!?

Black has three popular replies.

A) 4...c5 (1,232 games)

White normally, and most-successfully, plays 5.Nf3, after which the line splits.

A1 5...cxd4 6.Nxd4, after which there is another split.

A1.1 6....0-0 7.Bg2 d5 8.0-0 dxc4 9.Qa4 scores 66% for White.

A1.2 6...Ne4 7.Qd3, with a further split: A1.2a 7...Qa5 8.Nb3 Nxc3 9.Bd2 scores 63% for White; A1.2b 7...Bxc3+ 8.bxc3 Nc5 9.Qf3 scores 59% for White; A1.2c 7...Nxc3 8.bxc3 Be7 9.Bf4 scores 67% for White.

A2 5...0-0 6.Bg2, after which there is another split.

A2.1 6...cxd4 7.Nxd4 is a transposition to A1.1.

A2.2  6...d5 7.dxc5 scores 74% for White.

A3 5...Nc6 6.Bg2 Ne4 7.Bd2 Nxd2 8.Qxd2 scores 54% for White.

A4 5...Ne4 6.Qd3 Qa5 (the much less-popular 6...cxd4 7.Nxd4 is a transposition to A1.2) 7.Qxe4 Bxc3+ 8.Bd2 Bxd2+ 9.Nxd2 scores 56% for White.

B) 4...0-0 (1,190 games)

White nearly always plays 5.Bg2, after which the line splits.

B1 5...d5 6.Nf3, after which there is another split.

B1.1 6...dxc4 7.a3, with a further split: B1.1a 7...Be7 8.0-0 scores 62% for White; B1.1b 7...Bxc3+ 8.bxc3 scores 55% for White.

B1.2 6...c5 7.dxc5 is a transposition to A2.2.

B1.3 6...c6 7.Qb3 scores 67% for White.

B2 5...d6 6.Qb3!? scores 83% for White.

B3 5...c5 6.Nf3, after which there is another split.

B3.1 6...cxd4 7.Nxd4 is a transposition to A1.1.

B3.2 6...d5 7.dxc5 is another transposition to A2.2.

C) 4...d5 (337 games)

White nearly always plays 5.Bg2, to which Black almost invariably replies 5...0-0, a transposition to B1. Second, but a long way behind in popularity, is 5...c6, against which 6.Qb3 scores 71% for White.