Advance Variation

By advancing 3. e5, White fixes the pawn structure at once, claiming space and taking the f6 square away from Black's king's knight. The chain resembles the Advance French, with two differences. Black's c-pawn has already spent a tempo on ...c6 and needs another to reach c5. The light-squared bishop, however, has not yet been shut in by ...e6. Black aims to bring that bishop out before closing its diagonal, then strike at d4, the foundation of White's chain, with ...c5 and follow-up pressure from ...Nc6. White tries to keep the e5–d4 wedge intact, exploit the extra space, and sometimes push kingside pawns to harass the bishop.

3...Bf5 is the main line, chosen in well over half of games. With the bishop outside the chain, Black can continue ...e6 and let the dark-squared bishop support ...c5. White's fourth move sets the tone. The Short Variation, 4. Nf3 e6 5. Be2, opts for calm development, often going on 5...c5 6. Be3, and was popularized by Nigel Short in the 1990s. The Van der Wiel Attack, 4. Nc3 e6 5. g4, hunts the bishop with pawns and became closely tied to Alexei Shirov. The Bayonet Attack, 4. g4, and the Tal Variation, 4. h4, named after Mikhail Tal, also go after the bishop directly, while 4. Ne2 (Bronstein Variation) and 4. b4 (Prins Attack) are less common tries.

3...c5, the Botvinnik-Carls Defense, plays the central break immediately and accepts that the c-pawn moves twice. Since White's e-pawn has also moved twice, Black does not actually lose time. The move invites 4. dxc5, after which the e5-pawn loses its support. Black can usually win the pawn back, as in 4...Nc6 5. f4 e6 6. Be3 d4 7. Bf2 Bxc5, although the light-squared bishop then remains behind its pawns. White may instead choose 4. Nf3 cxd4 5. Nxd4. In the database Black scores slightly better after 3...c5 than after 3...Bf5. 3...e6 is a rarer choice, and 3...g6, 3...Na6 and 3...Qb6 are minor sidelines.

For many years 3. e5 was considered harmless, chiefly because Capablanca won convincingly against Nimzowitsch at New York 1927. A range of new ideas, from positional to openly aggressive, revived the move. By the 21st century it had become the most popular way of meeting the Caro-Kann. Overall results are almost even, and the engine gives White only a slight edge.