Exchange Variation, Positional Variation

With 5. Bg5, the standard move after the central exchange, White pins the f6-knight and threatens to win material. The threat is 6. Bxf6 followed by 7. Nxd5, or else forcing Black to accept doubled isolated pawns. Black most often answers with 5...Be7, breaking the pin. Next in frequency is 5...c6, which protects d5 directly. The two replies usually merge into the same positions. The counterpin 5...Bb4 appears in about a tenth of games. A model setup runs 5...c6 6. e3 Be7 7. Bd3 Nbd7 8. Qc2 O-O 9. Nge2 Re8 10. O-O Nf8 11. f3, which prepares e4; if White plays 9. Nf3 instead, h3 often follows.

Within 5...c6 there are several branches. The Reshevsky Variation, 6. Qc2, frequently transposes back to the main lines. The line 6. e3 Bf5 7. Qf3 Bg6 8. Bxf6 Qxf6 9. Qxf6 gxf6 heads for an early queenless middlegame. After 5...Be7, the Carlsen Variation, 6. e3 h6 7. Bh4 Bg4, develops the c8-bishop to g4 immediately. The engine rates the position as close to level, and White's practical results are somewhat better.