Vienna Game: Stanley Variation, c6 — How White Plays It

By playing 4.d4, you claim space in the centre and challenge Black's plan. Black's 3...c6 was meant to prepare d5, but your d4-pawn push gets there first — now Black must react. The engine's clear preference is to capture: exd4 scores 56.7% for White and leads to the line 4...exd4 5.Qxd4 Be7 6.Nf3. Notice that after 5.Qxd4 you have a comfortable queen in the centre and easy development, while Black's knight on f6 is a target. If Black instead tries to hold the centre with d5 — the second most popular move with 28,440 games — you still score 57.6%. The key is that you have the initiative; Black is already reacting to your centre break.

Here's how your winning chances look against each of Black's main choices at this position: - exd4 (30,465 games, White scores 56.7%): Capture with your queen and develop naturally — this is the engine's best path. - d5 (28,440 games, White scores 57.6%): Black finally pushes, but you're well-placed to respond. Your bishop on c4 eyes the kingside, and you can develop with tempo. - Bb4 (4,965 games, White scores 54.0%): Black pins your knight. Your score dips slightly but you're still well above 50%. - b5 (4,829 games, White scores 58.1%) and d6 (3,577 games, White scores 58.7%) and Bd6 (2,871 games, White scores 59.2%): These all score even better for you — and as we'll see, some of them are outright mistakes.

Three of Black's common replies are genuinely bad, and the drill will teach you to punish them: - b5 is an inaccuracy, losing about half a pawn compared to exd4. In practice you score 58.1% — Black wastes time pushing a pawn when they should be developing. - d6 is a mistake costing Black roughly 1.1 pawns of advantage. It's a passive, timid move that gives up the centre, and you score 58.7% in response. - Bd6 is also a mistake (losing about 1.0 pawns). Black develops the bishop to a passive square, blocking their own d-pawn. You score a healthy 59.2% from here. Against all three, stay active: keep the centre, develop with tempo, and don't let Black consolidate.

After the correct continuation 4...exd4 5.Qxd4, you get a pleasant asymmetrical centre. Your queen on d4 eyes both wings, your bishop on c4 is active, and your knight on c3 supports the centre. Black's knight on f6 is a natural target for your bishop or future g5-pawn push. If Black plays d5 later, your bishop can retreat to b3 or even take on d5 if the timing is right. The typical middlegame sees you with a slight space advantage and easier piece play — exactly the kind of edge a club player can convert.