Chessy
Petrov's Defense: Modern Attack: 3...Nc6 — How to Punish Black from Move 4
You've played 1.e4 e5 2.Nf3 Nf6 3.d4, and Black answers with 3...Nc6. This is the Modern Attack of Petrov's Defense, and after 4.dxe5 you've reached a critical early crossroads. The engine rates this position +1.08, a clear advantage for you as White — this is not a small edge, it's a real plus you can build on. The statistics across over a million games back that up: you win 57.4% of the time from here, with only 39.0% of games going to Black. The trick is knowing which of Black's replies to fear and which to punish. The drill below will sharpen your instincts.
Play the Petrov's Defense: Modern Attack: Nc6 against the engine
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Ready to put this into practice? Head to the board and test yourself against the engine's reply to 4.dxe5. Punish 4...Nxe5 and 4...Bb4+ on sight!
Create a free account →What You're Fighting For: The e5 Pawn and the Initiative
The move 4.dxe5 does more than just win a pawn temporarily. It rips open the centre while Black's knight on f6 is still undeveloped. Black has several ways to react, but the engine's best answer — Nxe4 — is also the most common, appearing in 877,216 games (about 80% of all encounters). From there, the engine line continues 5.Qe2 Nc5 6.Nc3, and you keep the pressure. Your queen eyes the e4-square, your knight develops with tempo, and Black's knight has been kicked back to c5 where it doesn't threaten much. The key idea: you aren't just grabbing a pawn — you're creating a position where Black's pieces lack harmony while your lead in development grows.
The Critical Moment: Black's Most-Played Replies
Here's how the most popular Black responses stack up, all with you playing White. Note which ones you should welcome and which deserve caution. - Nxe4 (877,216 games): White scores 56.2%. This is Black's best try, but you still come out ahead. Follow the engine's line: Qe2, threatening the knight, then Nc3 to develop. - Ng4 (102,490 games): White scores 51.4% — your smallest edge among the common replies. Still favourable, but be alert: Black is targeting your e5 pawn. - Nxe5 (81,691 games): White scores a massive 72.4%! This is a known mistake that loses about 2.4 pawns worth of advantage. Black grabs the wrong pawn and leaves their position in tatters. - Ng8 (15,533 games): White scores 61.3%. Also a mistake (losing roughly 1.4 pawns) — Black retreats and loses time. - Bb4+ (4,838 games): White scores an incredible 80.1%! This is a blunder that loses about 3.2 pawns. Black checks while your simple Bd2 or Nc3 block gains development. - Nh5 (3,317 games): White scores 70.1% — Black sidelines the knight and you develop freely.
Three Mistakes Black Makes Most Often
The database reveals three clear blunders you should know how to punish. 1. Nxe5 — This is the most common mistake (81,691 games). Black takes your e5 pawn, but at a huge cost: the engine says it loses ~2.4 pawns of advantage. After Nxe5, you simply take the knight with Qxd8+ Kxd8, leaving Black's king in the centre, exposed, and you can follow up with Nc3 with a dominant position. 2. Ng8 — Black undevelops completely. This mistake costs about 1.4 pawns. You simply continue exf6, winning a clean pawn since Black's knight on g8 has to come back out all over again. 3. Bb4+ — The worst offender at ~3.2 pawns lost. Black drops a bishop in most lines after you block with Bd2 or Nc3. If Bd2, then Bxd2+ Nxd2, and Black has traded their best piece for your bishop while you develop a knight to a great square.
The Engine's Recipe: Best Play from Move 4
Let's walk through the engine's top choice for both sides so you know what a perfect White setup looks like. 4.dxe5 Nxe4 (Black's best try). 5.Qe2! — This is the key move. It attacks the knight on e4 and prevents Black from safely capturing on e5. If 5...Nc5 (the engine's recommendation), then 6.Nc3 and you're already ahead. Your queen covers e4, your knight develops, and Black's knight on c5 is poorly placed. Black's alternatives aren't great: - 5...Nf6? drops the e5 pawn after 6.Nc3 and 7.Nd5 with immense pressure. - 5...d5? runs into 6.exd6 Bxd6 7.Nc3, and Black's king is stuck in the centre. Your takeaway: develop naturally, keep the queen active, and don't rush to exchange. The advantage will grow.
Results across 1,094,766 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| Nxe4 | 877,216 | 56.2% |
| Ng4 | 102,490 | 51.4% |
| Nxe5 | 81,691 | 72.4% |
| Ng8 | 15,533 | 61.3% |
| Bb4+ | 4,838 | 80.1% |
| Nh5 | 3,317 | 70.1% |
Frequently asked questions
Is 3...Nc6 in Petrov's Defense a mistake for Black?
Not a mistake — the engine rates the position after 4.dxe5 at +1.08 in White's favour, but Black has several playable options, especially 4...Nxe4. However, many Black replies (like 4...Nxe5, 4...Ng8, and 4...Bb4+) are clear mistakes or blunders that give White a very large advantage.
What is White's best move after 4.dxe5 Nxe4?
The engine's top choice is 5.Qe2, which attacks Black's knight on e4 and stops Black from recapturing the e5 pawn. After 5...Nc5, White plays 6.Nc3 with a strong position. White scores 56.2% from this line across hundreds of thousands of games.
Why is 4...Nxe5 a mistake in this position?
When Black plays 4...Nxe5, they lose about 2.4 pawns of advantage compared to the best move (4...Nxe4). White simply captures the knight with 5.Qxd8+ Kxd8, leaving Black's king exposed in the centre. White then develops with Nc3 and has a commanding lead. White wins 72.4% of games after 4...Nxe5.
How should White handle 4...Bb4+ in Petrov's Modern Attack?
4...Bb4+ is a blunder that loses roughly 3.2 pawns. White can block with 5.Bd2 or 5.Nc3. After 5.Bd2 Bxd2+ 6.Nbxd2, White has developed two pieces and Black has traded their bishop for a bishop. White scores a crushing 80.1% after this Black move.