The Nimzowitsch Defence is a somewhat unusual chess opening characterised by the moves:
- 1. e4 Nc6
This opening is an example of a hypermodern opening where Black invites White to occupy the centre of the board at an early stage with pawns. Black's intent is to block or otherwise restrain White's central pawns and, if allowed to do so by inaccurate play by White, eventually undermine the White pawn centre by well-timed pawn advances of his own or by attacking the White pieces defending the centre. World Champion Garry Kasparov and Grandmaster Raymond Keene wrote that it "has never been fully accepted as a dependable opening. Nevertheless it is sound and offers the maverick spirit a great deal of foreign territory to explore."
The Nimzowitsch is included under code B00 ("uncommon king's pawn opening") in the Encyclopaedia of Chess Openings.
- 2.d4 d5. The line that Aron Nimzowitsch, the originator of the opening, usually preferred. Now White can choose among (1) 3.e5, which Black usually meets with 3...Bf5, (although 3...f6 is also a decent, though more complex, variation) followed by playing ...e6 (which no longer locks in the light-squared Bishop) and later attacking White's central pawn chain with moves such as ...f6 and ...c5; (2) 3.exd5 Qxd5, followed by either 4.Nf3, seeking to gain time by attacking the queen with Nc3, but enabling Black to put pressure on White's centre with 4....Bg4 or 4....e5, or else 4.Nc3 Qxd4 5.Qe2, a risky gambit that can be dangerous to unprepared defenders; and (3) 3.Nc3 dxe4 (3...e6 leads to a type of French Defence) 4.d5 Ne5, when White usually continues with 5.Qd4 or 5.Bf4 Ng6 6.Bg3.
- 2.d4 e5. A solid line favored by the late British Grandmaster Tony Miles. White can transpose to the Scotch Game with 3.Nf3, or play 3.d5 Nce7 (3...Nb8, although perhaps not as bad as it looks, is considered inferior), which gives White only a slight plus score in practice. Another approach is 3.dxe5 Nxe5, when White can seek a quiet positional advantage with 4.Nf3 or play the more aggressive (but potentially weakening) thrust 4.f4.
- 2.Nf3, shown by some databases to be the most common move, is often played by White players not eager for a theoretical battle on their opponents' turf. 2...e5, transposing to a double king-pawn opening may be the best move, but is unlikely to appeal to the hard-core Nimzowitsch player. Other moves, including 2...d6, 2...e6, 2...Nf6, 2...d5, and 2...g6 are playable but tend to lead to inferior variations of the Pirc Defense, French Defence, Alekhine's Defence, Scandinavian Defense, or Robatsch Defense, respectively. The sharp 2...f5, the Colorado Gambit, although somewhat dubious, was played with some success by the American International Master Doug Root, and more recently by the Finnish International Master Olli Salmensuu and others. It may lead to wild complications, e.g. 3.exf5 d5 4.Nh4!? e5!? 5. Qh5+ g6 6.fxg6 Nf6! 7.g7+ Nxh5 8.gxh8(Q) Qxh4 9.Qxh7 Nd4, when White is a whole rook up, but Black has a huge lead in development and White's king is in jeopardy. Naiditsch-Doettling, Dortmund 2000, ended in a draw after further complications: 10.Qg6+ Kd8 11.d3 Nf4! 12.Qf7 Bb4+ 13.c3 Bg4! 14.Qg8+ Kd7 15.Qg7+ Kc6 16.g3 Nf3+ 17.Kd1 Nd4+ 18.Kd2 Nf3+ 19.Kd1 Nd4+ 1/2-1/2. The British International Master Gary Lane advocates the more solid 4.d4 Bxf5 5.Bb5 (trying to control the weakened e5 square) Qd6 6.Ne5 Nf6 7.0-0 Nd7 8.Bxc6 bxc6 9.Qf3! Nxe5 (or 9...e6 10.g4 Bg6 11.Nxg6 hxg6 12.Bf4 Qb4 13.Qd3) 10.Qxf5 Nf7 11.Bf4 Qd7 12.Qxd7+ Kxd7 13.Nd2 when Black's inferior pawn structure gave White a small advantage in Shaw versus Salmensuu, European Team Championship, León 2001 (1-0, 63).