Chess Opening Theory/1. d4/1...d5/2. c4/2...c6/3. Nc3/3...Nf6

Slav defence D10 Slav defence 3...Nf6 Black develops a knight to f6, and puts pressure on the e4-square. From here White has multiple good responses, although 4. Bf4 and 4. Bg5 should be avoided as Black can play 4...dxc4 and retain the pawn without giving White any compensation. /4. Nf3/ develops the White's knight to f3, increasing control over the d4 and e5 squares. This is considered the mainline and it gives Black many responses to choose from. /4. e3/ is similar to the Quiet variation, which occurs after 3. Nf3 instead. It disallows the Slav accepted with 4...dxc4 and forces Black into a different variation like the Semi-Slav or the Chebanenko Slav. It is however possible for Black to play 4...Bf5 and sacrifice a pawn. This move is usually followed up by 5. Nf3, although occasionally Nf3 is delayed in favour of other developing moves such as Qc2. /4. cxd5/ is occasionally played, relieving tension in the center, and play transposes to exchange Slav variations. Theory table Slav accepted 4. Nf3 dxc4 Semi-Slav defence 4. ... e6 4. e3 e6 Exchange variation 4. cxd5 cxd5 References Queen's Gambit Declined