Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. d4/3...exd4/4. Nxd4/4...Bc5/5. Be3

Classical variation C45 Scotch game → 4. Nxd4 → Classical variation 5. Be3 White defends the knight and relieves the pressure on f2. White threatens a tactic to win a piece: if, say, 5...Nf6?? 6. Nxc6! trades with tempo on Black's queen, and discovers an attack on the bishop. 6...dxc6 7. Qxd8+ Kxd8 8. Bxc5 +++. 5...Qf6 is the main move, adding pressure to f2 and another attacker to White's knight, which White defends with 6. c3. 6. Nb5?!, the Blumenfeld attack, which lays some traps and threatens Nxc7+ to win the rook, is inferior due to the continuation 6...Bxe3 (threatening 7...Qxf2#) 7. fxe3 Qh4+ 8. g3 Qxe4, and if 9. Nxc7+ Kd8 10. Nxa8 White's knight is trapped and Black can pick up a rook themselves with 10...Qxh1. 5...Bb6 is sometimes played by black, usually because they found the tactic but don't know or don't want to do the main line. White's best move is 6. Nf5, where they attack g7, protecting the bishop without damaging pawn structure, and also allowing a potential reroute to the square e3 later. Theory table 5. ... Qf6 6. c3 Nge7 7. Bc4 Classical variation + 5. ... ... 6. Nb5 Bxe3 7. fxe3 Qh4+ 8. g3 Qxe4 9. Nxc7+ Kd8 10. Nxa8 Qxh1 Blumenfeld attack - References See also