Opening guide

Playing Black in the English Opening: Agincourt Defense Nf3

ECO A13 316,714 games Stockfish +0.32

After 1.c4 e6 2.Nf3 Nf6, you've entered the Agincourt Defense — a solid, flexible setup that aims to neutralise White's first-move advantage before counterpunching in the centre. The engine gives White a tiny edge (+0.32), and across over 316,000 games Black scores a respectable 44.6% here. This page shows you what to expect against White's most popular replies, and points out the one move your opponent should never play. Jump into the interactive drill below to try the position yourself.

On this page
  1. Practice against the engine
  2. What You're Fighting For
  3. The Critical Tabiya: White's Most Popular Replies
  4. The One Move Your Opponent Might Blunder
  5. How the Engine Punishes d3
  6. Real-game results
  7. FAQ
  8. More English lines

Play the English Opening: Agincourt Defense: Nf3 against the engine

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What You're Fighting For

The Agincourt Defense is all about symmetry and patience. By playing 1...e6 and 2...Nf6, you keep the centre flexible: you're ready to meet d4 with ...d5 (reaching a Queen's Gambit Declined structure), or to fianchetto your queen's bishop and build a solid, hypermodern setup. Your main idea is to let White commit to a central pawn structure first, then challenge it. Statistically, you win 44.6% of the time from here — and with White's edge at just +0.32, you're never worse than slightly uncomfortable.

The One Move Your Opponent Might Blunder

Among all the moves White can play, one stands out as a clear mistake: d3. It's an inaccuracy that costs White roughly 0.6 pawns in engine evaluation. Across only 8,461 games, White's score drops to 46.0% — the only move where White wins less than half the time. If you see 3.d3, you should be encouraged: you're already doing better than the statistics suggest. The engine's recommendation here is g3, so if White plays d3 instead, they've given away a chunk of their opening advantage. Develop naturally (3...d5 or 3...c5) and the position will favour you.

How the Engine Punishes d3

Let's be concrete: after 3.d3, the engine's best move is 3...g3. Wait — that's White's best move, not yours. Sorry for the confusion. What the engine means is that White should have played g3 instead of d3. From Black's perspective, after 3.d3, simply continue developing: 3...d5 and aim to complete development. The point is that White's pawn on d3 blocks their own dark-squared bishop and doesn't help contest the centre. Black's score already jumps to 54.0% (since White's win rate drops to 46.0%). Keep it simple — build your centre and finish your development before launching any attacks.

Results across 316,714 Lichess games

51.2%
4.2%
44.6%
White 51.2% Draw 4.2% Black 44.6%
Most-played continuationGamesWhite wins
1 Nc3Main line 99,314
50.7%
2 d4 84,958
50.6%
3 g3 77,305
53.4%
4 e3 23,577
50.2%
5 b3 12,544
55.1%
6 d3 8,461
46.0%

Frequently asked questions

Is the English Opening: Agincourt Defense Nf3 good for Black?

Yes, it's a perfectly sound opening for Black. The engine gives White only a +0.32 advantage, and Black wins 44.6% of games from this exact position. You're slightly worse but very much in the game, with lots of room to outplay your opponent in the middlegame.

What is the best reply to 1.c4 e6 2.Nf3 Nf6?

White's engine-approved best move is 3.g3, scoring 53.4% for White. But more common are 3.Nc3 and 3.d4, both scoring around 50.7%. The move to hope for is 3.d3, which is an inaccuracy that drops White's win rate to just 46.0%.

Should Black play ...d5 or ...b6 after 3.g3?

Both are playable, but the engine's recommended setup after 3.g3 is 3...b6 followed by 4...Bb7, fighting for the long diagonal against White's Bg2. This is the standard Agincourt fianchetto plan. If you prefer a more classical approach, 3...d5 is also fine.

Why is 3.d3 a mistake for White?

White's d3 blocks the dark-squared bishop and fails to challenge the centre effectively. The engine says White loses about 0.6 pawns of advantage compared to the best move (g3). Statistically, White's win rate drops to 46.0% — the only sub-50% score among White's options.

How many games feature the English Opening: Agincourt Defense: Nf3?

Over 316K Lichess games have reached the English Opening: Agincourt Defense: Nf3 position. White wins 51.2%, Black wins 44.6%, with 4.2% draws — based on real rated games.