Chessy
How to Play the Polish Opening: Czech Defense Nf3 as Black
After the moves 1.b4 e5 2.Bb2 d6 3.Nf3 Nf6, you've reached a solid spot as Black in the Polish Opening. Despite the unusual first move, White has committed to a flank attack — and your job is to claim the centre and develop naturally. The engine calls this position dead level: neither side is better out of the opening, so the real fight starts now. Scroll down to play through the key lines, see what the statistics say, and learn which White moves you should welcome — and which ones you need to punish.
Play the Polish Opening: Czech Defense: Nf3 against the engine
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The Polish Opening starts with 1.b4 — an immediate grab of queenside space. With your reply 1…e5, you seize the centre, and after 2.Bb2 d6 3.Nf3 Nf6, both sides have their pieces aimed at the middle. You've developed a knight and fianchettoed your opponent's bishop has a long diagonal, but it's currently blocked by your pawn on d6. Your plan from here is straightforward: keep central control, finish development, and gradually exploit the fact that White's b4-pawn has weakened the queenside light squares. The engine rates this -0.13, a tiny edge for you — essentially equal. In practice, your winning chances are very real: out of nearly 47,000 games from this position, Black scores 47.7% wins to White's 48.2%.
The Engine's Best Answer
Stockfish suggests White should play 4.c4 here, continuing with c4 e4 Nd4 c5. That line fights for a space advantage and aims to challenge your centre. From your perspective, you should be fine — you simply reply with 4…e4, kicking the knight, and after 5.Nd4 c5 you've opened lines for your pieces and gained time. This is a principled approach: counter-attack in the centre when your opponent plays on the flank. The engine line is not the most popular human move, but it's worth knowing because it represents White's toughest test.
What the Statistics Reveal
The database of 46,794 games shows exactly which White moves you're likely to face and how they score. Here are the most common continuations from this position: - 4.e3 (26,138 games, 49.3% for White): A quiet developing move. Black is fine — just play naturally with Be7, 0-0, and maybe Re8 or Nbd7. - 4.d3 (4,627 games, 48.3% for White): The engine's recommended alternative to g3. This is solid for White. - 4.g3 (2,982 games, 53.7% for White): This is the move to watch out for — White scores best here, but it's actually an inaccuracy. More on that below. - 4.d4 (2,730 games, 44.0% for White): A poor move that gives Black good chances. You should be happy to see this. - 4.c4 (2,400 games, 46.1% for White): The engine's top line, yet humans don't score well with it — Black has comfortable play.
Punishing White's Mistakes: g3 and d4
Two common White moves deserve special attention. 4.g3 is an inaccuracy that loses about 0.6 pawns — the engine says d3 was better. You can respond actively: after 4…Be7 and a timely …e4 push, the g3 fianchetto leaves the kingside slightly airy. Your plan is straightforward: develop, castle, and look for central breaks. 4.d4 is worse — a full mistake costing White roughly 1.1 pawns in evaluation. Here you can strike immediately with 4…exd4 5.Bxd4 (or 5.Nxd4) and then continue with c5, Nc6, or Bg4 depending on the reply. The statistics back this up: White scores just 44.0% from 4.d4, the worst result of any common move. Recognise these moments and you'll convert a clear edge.
Typical Middlegame Ideas
From this position, Black's game practically plays itself. Your knight on f6 eyes the centre, your d6 pawn supports …e5 and later …c5 breaks, and your king will be safe after castling kingside. A typical plan: develop the light-squared bishop to e7 or g4, play …Nbd7 (or …Nc6 if the d4 square is available), and prepare …c5 or …d5 to challenge White's centre. If White plays quietly (like 4.e3), you can aim to build a strong centre with …c6 and …d5, or even …Bf5 and …Qd7. The position is rich but forgiving — you won't be punished for one inaccuracy, though White might. Just remember: occupy the centre, finish development, and trust that 1.b4 didn't do White any favours.
Results across 46,794 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| e3 | 26,138 | 49.3% |
| d3 | 4,627 | 48.3% |
| g3 | 2,982 | 53.7% |
| d4 | 2,730 | 44.0% |
| c4 | 2,400 | 46.1% |
| h3 | 1,632 | 46.8% |
Frequently asked questions
Is the Polish Opening good for Black?
Yes, Black is doing very well in this line. The engine evaluates the position at -0.13, which is essentially equal. In practice, Black wins 47.7% of games from this exact position, almost matching White's 48.2% win rate — and that gap is tiny for an opening where White has the first move.
What is the best response to 1.b4 as Black?
The most principled reply is 1…e5, striking in the centre immediately. After 2.Bb2 d6 3.Nf3 Nf6, you've reached the position covered here. Black has comfortable development and no weaknesses. The statistics confirm this is a solid choice.
Should I be afraid of 4.g3 in the Polish Opening?
No, you should be alert but not worried. White scores 53.7% from 4.g3, which is the highest of any move, but the engine calls it an inaccuracy — it loses about 0.6 pawns compared to the better 4.d3. Play natural moves like Be7 and watch for the …e4 break to gain space and time.
How do I punish 4.d4 in this line?
Take the pawn: 4…exd4. After White recaptures with the bishop or knight, you continue developing with …c5, …Nc6, or …Bg4. The statistics show White scores only 44.0% from 4.d4, the worst of any common move, and the engine says it's a mistake costing about 1.1 pawns. You're clearly better.