Panov Attack, Modern Defense

The Modern Defense, 5...Nc6, brings the queen's knight out before the e-pawn moves, so Black targets d4 at once instead of first bolstering d5 with 5...e6. Opening references describe it as Black's most ambitious fifth move but also a risky one, because d5 has no pawn support and White can try to exploit that. The usual reply is 6. Nf3, which protects d4. Black can then play 6...Bg4, the Mieses Line, which pins the knight and adds to the pressure on the center. The second most common reply, 6. Bg5, goes after the f6-knight that guards d5. Against it, 6...e6 (the Carlsbad Line) reinforces the pawn, while 6...Qa5 (the Czerniak Line) and 6...Qb6 (the Reifir-Spielmann Line) answer with queen counterplay, the latter hitting b2 and d4. The rarer 6. cxd5 can transpose to the 6. Nf3 lines, though Black can keep the game independent with 6...Bf5.

In the Lichess database White scores slightly better than Black and draws are uncommon. The engine rates the position as roughly balanced and prefers 6. Nf3, 6. cxd5 and 6. Bg5.