Standard Defense

The Standard Defense, 1. e4 g6 2. d4 Bg7 3. Nc3 d6, is the main line of the Modern Defense, also known as the Robatsch Defense. Black lets White keep the classical e4/d4 pawn duo. With 3...d6 Black covers e5, opens the diagonal of the c8-bishop, and prepares to strike at the center with ...e5 or ...c5 rather than occupy it. It is the most common answer to 3. Nc3. The alternatives are 3...c6, which is considered more passive, and the riskier 3...c5. Because the knight is still on g8, Black can enter a Pirc at any point with ...Nf6. Black can also stay in Modern territory with queenside setups based on ...c6 or ...a6.

The resulting structure is typical of hypermodern play. White has more space and central control and aims to use it before Black's counterplay begins. Black's pieces, especially the g7-bishop, are aimed at d4. The game turns on whether Black can break with ...e5 or ...c5 at a moment when White's center cannot be held or advanced profitably. If Black fails to generate such counterplay, White's space advantage tends to become decisive, so Black's choice of setup has to fit White's fourth move.

4. Be3 is the most popular reply and is also the engine's first choice. White develops a piece that reinforces d4 and leaves the choice of king position and kingside pawn moves open. The engines also rate 4. f3 highly. It buttresses e4 in advance, so that a later ...Nf6 does not gain time, and it rules out ...Bg4. 4. Nf3, the Two Knights Variation, is the quieter classical development. 4. f4, the Pseudo-Austrian Attack, is the most ambitious attempt to claim space; the name reflects its similarity to the Pirc's Austrian Attack without Black's knight yet on f6. The standard response there is 4...c6 5. Nf3 Bg4. Black pins the knight that supports d4 and the e5 square before deciding on further development.

The position is among the most frequently reached named openings, with close to 80,000 Lichess games. White scores somewhat better than Black, and draws are unusually rare at under four percent, which reflects the unbalanced, fighting character of the play. Engines assess White as holding a slight edge, the usual verdict for Black systems that concede the center. Theory is less forcing than in the sharpest main lines, but frequent transpositions to the Pirc and to other Modern setups mean both sides need to know the related structures.