Chessy
Indian Defense: London System – Playing Against 4...Nc6
You have opened with 1.d4 Nf6 2.Nf3 e6 3.Bf4 Nc6 4.e3, and the position is balanced — the engine evaluates this at +0.39, a small but real edge for White. That means you are doing fine, and with accurate play you can maintain the pressure. Black has multiple ways to respond, and knowing which replies score well for you — and which common mistakes to punish — turns this tiny plus into a steady advantage. Below the drill, you will see exactly what works and what you should watch for.
Play the Indian Defense: London System: Nc6 against the engine
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Play through these lines against the adaptive engine below — practise your responses to 4...d5, 4...Bb4+, and every other Black reply until the +0.39 edge feels
Create a free account →What You Are Fighting For
The London System setup with Bf4 aims to build a solid pawn centre (d4 and e3) while keeping the dark-squared bishop active outside the pawn chain. Black's unusual move 4...Nc6 challenges your centre immediately — the knight eyes d4 and also supports an immediate ...d5 or ...e5 break. Statistically, you are doing well here: over 331,724 games from this exact position, White wins 55.4% of the time, with only 3.9% draws. That high White win-rate tells you Black's position is trickier to handle than it looks. Your goal is to develop naturally, keep the centre stable, and wait for Black to commit to a structure you can exploit.
The Engine's Favourite Reply: 4...Bd6
When you play 4.e3, the engine's best move for Black is Bd6, immediately challenging your dark-squared bishop. The recommended line continues Bd6 Bg5 h6 Bh4 — Black trades light pieces and gains a tempo with ...h6. Even in this sharpest line, the evaluation stays at +0.39, meaning you are still slightly better. Across 23,377 games where Black chose 4...Bd6, White scores 56.1%, a touch above the overall average. The lesson: do not fear this exchange. After ...Bd6, simply retreat your bishop to g5 or h4, develop your other pieces, and trust that your centre and space advantage remain intact.
The Most Common Moves and How They Score
Black has several popular replies, and the statistics show clear trends. Here are the top continuations and your winning chances in each: - 4...d5 (91,405 games): the most popular move; White scores 55.7%. Black claims central space, but your Bf4 stays active and you can play c4 later. - 4...Bb4+ (51,537 games): White scores 57.9% — your best result. You answer c3 or Bd2 simply, and Black's bishop is misplaced once you push d4-d5. - 4...Be7 (31,335 games): White scores 54.2%. Black plays solidly but lets you keep the bishop on f4 without harassment. - 4...d6 (26,399 games): White scores 53.3%. Black prepares ...e5, but you can meet it with dxe5 and keep a good structure. - 4...b6 (20,224 games): White scores 52.9%. Black fianchettoes early; your queen's knight can go to c3, and you may target the dark squares. Every line gives you above 50% — there is no dangerous equaliser for Black in this position.
The Critical Mistake to Punish
While no specific mistake for Black is listed in this position, the most dangerous idea you must anticipate is an early ...d5 followed by ...e5, breaking open the centre while your knight is still on f3 and your king is uncastled. Many club players try to chase your Bf4 with ...g5 or ...h6 prematurely. Do not panic — retreat the bishop to g3 or h4 as needed, answer ...g5 with Bh4, and castle quickly. Your biggest responsibility is to avoid moving the same piece twice while behind in development. If Black wastes time attacking your bishop, you gain a lead in development and the +0.39 edge grows. Stay calm, finish your kingside castling, and the position plays itself.
Results across 331,724 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| d5 | 91,405 | 55.7% |
| Bb4+ | 51,537 | 57.9% |
| Be7 | 31,335 | 54.2% |
| d6 | 26,399 | 53.3% |
| Bd6 | 23,377 | 56.1% |
| b6 | 20,224 | 52.9% |
Frequently asked questions
Is 4...Nc6 a good move against the London System?
Statistically it is playable but not dangerous for White. Across over 330,000 games White wins 55.4% of the time. The engine gives White a +0.39 edge. Black's knight on c6 can become a target if you push d5 later.
What is the best response to 4...Bb4+ in the London System?
Interpose with either c3 or Bd2 — both are fine. In practice, after 4...Bb4+ White scores 57.9%, your best result among all of Black's replies. The check is more annoying than dangerous, and Black's bishop may end up misplaced.
Should I play c4 right away against 4...Nc6?
Not immediately. Your setup with 4.e3 is solid, and you should develop your queen's knight to c3 or d2 first. A premature c4 can allow Black to strike in the centre with ...d5 or ...e5. Let the position unfold before committing the c-pawn.
What does the engine recommend after 4.e3 Nc6?
The engine's best line for Black is 4...Bd6, challenging your Bf4. The suggested continuation runs Bd6 Bg5 h6 Bh4. Even in that line White keeps a +0.39 advantage, so you do not need to fear the bishop trade.
How many games feature the Indian Defense: London System: Nc6?
Over 331K Lichess games have reached the Indian Defense: London System: Nc6 position. White wins 55.4%, Black wins 40.7%, with 3.9% draws — based on real rated games.