Modern Variation

The Modern Variation, 1. b3 e5, is Black's most frequent and most ambitious answer to the Nimzo-Larsen Attack. The e-pawn takes a central square immediately and blocks the long diagonal that White has just prepared to use. The position mirrors Owen's Defense (1. e4 b6) with colors reversed and White a move ahead, and some commentators doubt that the spare tempo makes that setup fully satisfactory. For this reason Nimzowitsch preferred reaching b3 via 1. Nf3 d5 2. b3, which rules out ...e5 altogether. The case for the direct move order is that, with the g1-knight still at home, White keeps f2-f4 in reserve as a way of challenging e5.

White replies 2. Bb2 in the overwhelming majority of games, hitting e5 at once. Black usually protects the pawn with 2...Nc6, while 2...d6 is an occasional, more passive choice. White must then decide whether to permit a broad pawn center or to prevent it. The patient 3. e3 opens the f1-bishop and allows ...d5, with the intention of attacking the pawns afterward from the flanks with c4 and f4. A typical illustration is 3...d5 4. Bb5 Bd6 5. f4, in which the pin on the c6-knight and the bishop's pressure toward g7 make e5 difficult to sustain.

The alternative 3. c4 stops ...d5 and produces a reversed Sicilian. Black can treat it in Open Sicilian fashion with 3...Nf6 4. e3 d5 5. cxd5 Nxd5, or in Closed Sicilian fashion with 3...g6. The Pachman Gambit, 3. f4, offers a pawn to break up the center at once and leads to sharper play.

Other second moves are uncommon. 2. e4 transposes to Charles' Opening, a King's Pawn Game in which Black scores better than in the main line, while 2. e3 and 2. g3 are rarely seen.

Engines rate the position as balanced. It is one of the more frequently reached named positions in online play, where White scores slightly better than Black and draws are unusually rare. The middlegames turn on structure rather than forcing theory: whether Black's central pawns become a source of space or a target for White's flank pawns and long-diagonal bishop.