Chessy
London System: Bg4 — How to Handle Black's Early Bishop Sortie
When Black pins your knight with 3...Bg4 in the London System, you have a sharp answer ready: 4.Ne5. This immediate thrust challenges the bishop and stakes a claim in the centre. With a Stockfish evaluation of +0.57, a clear edge for White, you are slightly better from the start. Across nearly 48,000 games White scores a solid 53.1%, with Black winning only 43.1%. The position calls for precise development — and one particular mistake from Black gives you a chance to seize an even bigger advantage. Play through the drill below and see how it feels.
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Create a free account →The Main Point: Why 4.Ne5 Works
The London System is known for its solid, reliable setup, but Black's ...Bg4 can feel annoying — it pins your knight to the queen. By playing 4.Ne5 you take immediate action. The knight attacks the bishop and threatens to capture it, forcing Black to decide what to do. If the bishop retreats or exchanges, you will have gained time and central control. The engine evaluates the resulting position at +0.57, a small plus for White, so you are already standing a little better. Black has to find accurate moves from here, and the statistics prove that many players do not.
Black's Most Popular Replies — and How You Score
Black has several reasonable-looking options here, and the database shows exactly how each one works out for you. Here is the top five most-played moves from this position, with White's winning percentage in parentheses: - e6 (53.3%) — Black prepares ...Bf5 or ...Be7. You continue naturally with e3, then develop your pieces. - Bh5 (50.5%) — The bishop sidesteps your knight. This is the toughest test, but you still score better than Black. - Bf5 (51.7%) — The engine's recommended move. Black puts the bishop outside the pawn chain. Your plan is e3, followed by Nd2 and c3, building a solid centre. - Nbd7 (54.6%) — A very popular choice among club players, but it is actually a mistake (more on that below). - Nc6 (56.4%) — Black develops and attacks your knight. This actually gives you your best score — you can trade on c6 or retreat and keep the tension. All of these replies leave you with a comfortable position and winning chances above 50%.
The Critical Mistake to Punish
Among Black's most played replies, one stands out as a clear blunder: 4...Nbd7. This move loses roughly 0.7 pawns in evaluation — a serious inaccuracy. The better move was 4...Bf5. Why is 4...Nbd7 so bad? It develops a piece but does nothing about the immediate threat to the bishop on g4. After 4...Nbd7, you can capture the bishop with 5.Nxg4, and if Black recaptures with 5...Nxg4, you have traded a knight for a bishop and forced Black to move the same knight twice — a clear gain in time and piece quality. In the 4,507 games where Black played ...Nbd7, you scored 54.6%, so it is worth knowing how to react. Whenever your opponent plays this move, take the free bishop.
A Simple Development Plan After 4...Bf5
When Black finds the engine's best reply, 4...Bf5, the game continues in a positional direction. Your setup is straightforward: develop with e3, then Nd2, then c3, and get your king castled. The pawn structure will be symmetrical for a while, but you have the extra space from the knight on e5. Black's bishop on f5 is well placed but not dangerous — it does not threaten anything immediately. You can aim to play f3 later or simply complete development and see what Black does. The engine line (Bf5 e3 e6 Nd2) shows a natural, calm approach that keeps your small edge. No fireworks needed — just good, solid chess.
Results across 47,916 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| e6 | 12,415 | 53.3% |
| Bh5 | 10,357 | 50.5% |
| Bf5 | 10,244 | 51.7% |
| Nbd7 | 4,507 | 54.6% |
| Nc6 | 4,114 | 56.4% |
| Be6 | 2,083 | 54.2% |
Frequently asked questions
Is 4.Ne5 in the London System a good move against 3...Bg4?
Yes. 4.Ne5 is the engine's top choice and gives White a clear advantage. Stockfish evaluates it at +0.57, a small plus for White, meaning you are slightly better. White scores 53.1% across nearly 48,000 games from this position.
What is Black's best reply to 4.Ne5?
Black's best move is 4...Bf5, which is the engine's recommended continuation. After that you can play e3, then Nd2, developing naturally. Black's other options like 4...e6, 4...Bh5, or 4...Nc6 are playable but give you even better winning chances.
Why is 4...Nbd7 a mistake in this position?
4...Nbd7 is an inaccuracy because it loses roughly 0.7 pawns. It does not address the immediate threat to the bishop on g4. You can simply capture with 5.Nxg4, and after 5...Nxg4 you have won a bishop for a knight and forced Black to waste time moving the same knight twice.
How should White continue after 4...Bf5?
The engine recommends a calm developing plan: e3, followed by Nd2 and c3. Do not rush — just complete your development, get your king to safety, and maintain your small edge. The position does not require any aggressive tactics; solid chess will keep you slightly better.