How to Play the Semi-Slav Defense: Accelerated Move Order (Nf3) as Black

By taking on c4 with 4...dxc4, you've grabbed a pawn and challenged White to prove they have enough compensation. This is the central idea of the Semi-Slav's accelerated move order: you delay committing your dark-squared bishop and keep the centre fluid. White's next move will reveal their intentions. If they play e4 (the most popular choice at 140,267 games), they try to seize a space advantage and reclaim the pawn quickly. If they play a4 (the engine's top pick), they prepare to recapture on c4 with the bishop after ...Bb4 and Bd2 — a more positional approach. Your task as Black is to develop efficiently, complete your kingside development, and either hold onto the extra pawn or return it under favourable circumstances.

Stockfish evaluates the position at +0.36, which means a small edge for White. That puts you, as Black, slightly worse from the start. But don't let that discourage you — a +0.36 edge is far from decisive, and the winning percentages confirm that Black scores a healthy 44.3% in practice (with 3.8% draws and 51.9% White wins). You have real counterplay, especially if White doesn't know the most accurate continuation. The engine's best move for White is a4, leading to the line a4 Bb4 Bd2 Nf6 — a calm, positional battle where you can aim to challenge the centre later with ...e5 or ...c5.

Let's look at White's most common choices and how you should react to each one: - e4 (140,267 games, White scores 50.7%): This is the most frequent move, and White's score is only slightly above 50%. That means you're doing fine. Develop with ...b5 and ...Bb7, or play ...Nf6 and ...Be7, keeping your extra pawn secure for now. - a4 (66,456 games, White scores 54.6%): The engine's top choice — and White's best practical score. Be ready to play ...Bb4 and after Bd2, go ...Nf6. White may regain the pawn soon, but you'll have a solid position. - e3 (57,141 games, White scores 51.8%): A quieter option. You can play ...b5 to protect your pawn, or develop with ...Nf6 and ...Bd6. - Bg5 (37,588 games, White scores 53.0%) and Bf4 (24,833 games, White scores 50.1%): These are covered in the next section — they are inaccuracies you can punish.

Both Bg5 and Bf4 are classified as inaccuracies in this position, losing roughly 0.5 and 1.0 pawns of advantage respectively (the engine says a4 was better in both cases). Here's what that means for you: - If White plays Bg5: They pin your knight before securing the c4 pawn. You can respond with ...b5 and ...Bb7 to reinforce your extra material, or play ...h6 to ask the bishop what it's doing. White's bishop on g5 is misplaced in this structure. - If White plays Bf4: This is an even bigger inaccuracy. The bishop does nothing useful on f4 — it doesn't prevent ...b5 or help reclaim the pawn. You can calmly play ...Nf6 and ...Bd6, aiming to trade off the f4-bishop. In both cases, your practical chances improve significantly, and the stats back this up: White scores only 50.1% with Bf4 — essentially no advantage at all.