Chessy
London System: Nc6 – A Small but Steady Edge for White
You've played 1.d4, 2.Nf3, 3.Bf4 — the London System. Instead of the more common setups, Black challenges you early with 3...Nc6, putting pressure on your dark-squared bishop and the d4 pawn. After 4.e3, it's Black's turn, and you've reached a tabiya played over 6,321,561 times. Stockfish gives you a +0.52 advantage — a small, durable edge. The drill below asks you to find the engine's top choice here, a move that keeps your initiative alive while punishing Black's aggressive knight development. Let's see how you handle it.
Play the London System: Nc6 against the engine
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Now it's your turn. Jump into the interactive drill and practice facing 3...Nc6 — the engine will adapt to your choices and help you find the best responses.
Create a free account →What Black Is After with 3...Nc6
Black's move 3...Nc6 is a direct challenge. Instead of playing ...e6 or ...c6 to build a solid QGD-style centre, Black develops a knight to its most active square. The knight attacks your d4 pawn and eyes the e5 outpost. If you react passively, Black can follow up with ...Bg4, pinning your f3-knight and increasing pressure on d4. In the London System, your setup with Bf4 already protects d4 indirectly, but Black hopes to disrupt you before you can play c3 and e3 to solidify. The good news: the statistics show you handle this well. Across over 6.3 million games at this exact position, White wins 54.3% of the time, compared to Black's 41.3%. You're already in a favourable spot — now you just need to pick the right continuation.
The Engine's Top Move: 4...Bg4 Met by 5.h3
The most popular Black reply in the database is 4...Bg4, played nearly 1.8 million times. Black pins your f3-knight to your queen, threatening to exchange off the knight and then put pressure on d4. Stockfish's best answer is 5.h3, a simple but effective push. Black's only sensible continuation is 5...Bxf3 (the bishop has no good retreat), then 6.Qxf3. Your queen steps to a commanding centralised square, and you've won the bishop pair in a position where your pawn structure is unblemished. White scores 53.3% from this line — a healthy, consistent plus. The key insight: don't fear the pin. Hitting the bishop immediately forces Black to trade a well-placed piece for your knight, and your queen ends up on a great square.
What the Other Popular Replies Tell You
Black can avoid the pin and choose a quieter path. The second most-played reply is 4...e6 (1.7 million games), which transposes toward a more standard Queen's Gambit Declined structure. Here White scores an even stronger 55.0%. Your plan is simple: develop naturally with your knight, bishop, and castle, keeping your central pawns flexible. The third option, 4...Bf5 (1.5 million games, White scores 54.8%), puts the bishop outside the pawn chain. You can challenge the bishop immediately — a classic London idea — and maintain a similar edge. Black's other tries — 4...a6, 4...h6, and 4...Ne4 — are less common and all score below 57% for White. Against 4...Ne4 specifically, White jumps to 56.9%, your best statistical outcome. In every case, you keep your small edge by sticking to London principles: secure the centre, develop the kingside, don't rush the attack.
The Mistake to Punish
Because your position is sound and Black has already committed a knight to c6, some aggressive but misguided Black moves can backfire. One pattern you'll see is Black trying to harass your bishop on f4 with a knight sortie. In the London System, your bishop is well placed there — if Black chases it, you can retreat it safely or play a2-a3 to kick the intruding piece, gaining time and keeping your structure intact. Another mistake: Black playing ...g6 to fianchetto without first challenging your centre. A fianchettoed bishop doesn't pressure d4, and you can continue building your standard London setup without disruption. The statistics confirm that your patient approach pays off — Black's win rate drops sharply when they play over-ambitious moves in the opening.
Results across 6,321,561 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| Bg4 | 1,781,284 | 53.3% |
| e6 | 1,711,679 | 55.0% |
| Bf5 | 1,526,699 | 54.8% |
| a6 | 390,617 | 52.4% |
| h6 | 218,695 | 54.6% |
| Ne4 | 190,588 | 56.9% |
Frequently asked questions
Is 3...Nc6 a good move for Black against the London System?
It's playable but not dangerous for White. The position scores 54.3% for White across over 6.3 million games, and Stockfish evaluates it at +0.52 — a small but clear edge. Black challenges your d4 pawn early, but you can maintain your advantage with simple developing moves like 4.e3 and then 5.h3 if Black plays ...Bg4.
What is the best way to respond to 4...Bg4 in the London System?
The engine's top move is 5.h3. After 5...Bxf3 6.Qxf3, you've traded a knight for Black's light-squared bishop and your queen sits on an active central square. White scores 53.3% from this position — a solid result. Don't be tempted to block the pin with a passive piece interposition first; h3 is the most forcing and effective reply.
How should White play against 4...e6 in this London System line?
After 4...e6, you have a standard London setup. Develop your knights and bishop naturally, castle, and play c3 to secure d4. White scores 55.0% from here — even better than against 4...Bg4. The key is to develop calmly; Black's knight on c6 doesn't threaten much once you secure d4 with c3.
Does the London System with 3...Nc6 favour White or Black?
It favours White slightly. The evaluation is +0.52, and White wins 54.3% of games with only 4.3% draws. While the London System is known as a solid, low-risk opening, this particular variation gives you a consistent advantage that you can nurse into the middlegame.