Lasker Trap: How It Works and How to Beat It
The Lasker Trap is one of the most famous opening traps in chess. In the Albin, Black underpromotes to a knight — a queen would fail — to win White’s queen. Here is the whole line, the exact moment it springs, and the refutation — from both sides of the board.
What the Lasker Trap is
First seen in master play more than 120 years ago, the Lasker Trap still scores at club level for one reason: it punishes a natural-looking move. In the Albin Counter-Gambit, Black underpromotes to a knight (...exd2 then ...d1=N!) winning material — one of the rare practical underpromotion traps.
Black is the side setting the trap. The plan in one line: In the Albin, Black underpromotes to a knight — a queen would fail — to win White’s queen.
How to see it coming
The trap announces itself early. The tell-tale sequence is 1.d4 d5 2.c4 e5 3.dxe5 d4 4.e3 Bb4+ 5.Bd2 dxe3 6.Bxb4 exf2+ 7.Ke2 — after which the position below appears. It is Black to move, and the trap is loaded. If you are the defender, this is the moment to slow down and calculate rather than reply on autopilot.
The trap, move by move
Here is the full main line — 16 moves from the starting position to the finish. The critical moment is 7… fxg1=N+: Underpromotion! A queen allows Qxd1 — but the knight comes with check.
| Move | What's happening |
|---|---|
| 1. d4 | Queen’s-pawn opening. |
| 1… d5 | Symmetric reply. |
| 2. c4 | The Queen’s Gambit. |
| 2… e5 | The Albin Counter-Gambit — Black counter-strikes. |
| 3. dxe5 | White takes. |
| 3… d4 | The advanced d-pawn is the soul of the Albin — cramping and venomous. |
| 4. e3 | Natural, but the losing move. Nf3! was right. |
| 4… Bb4+ | Check, exploiting the undefended back rank. |
| 5. Bd2 | Blocking. |
| 5… dxe3 | Black ignores the bishop and pushes into White’s camp. |
| 6. Bxb4 | White grabs the bishop, expecting …exf2+ to be harmless… |
| 6… exf2+ | Check! |
| 7. Ke2 | The king steps out. |
| 7… fxg1=N+ | Underpromotion! A queen allows Qxd1 — but the knight comes with check. |
| 8. Rxg1 | White must take the new knight… |
| 8… Bg4+ | …and this check wins White’s queen. Black emerges on top. |
And the position at the end — …and this check wins White’s queen. Black emerges on top.
How to spring it (as Black)
If White lazily plays e3 against your Albin d-pawn, strike: …Bb4+ Bd2 dxe3! Bxb4 exf2+ Ke2 fxg1=N+! — underpromote to a knight (a queen fails) and …Bg4+ wins the queen. One of the only practical underpromotion traps.
How to defend against it (as White)
The Albin’s d4-pawn is poison — do NOT play e3?? against it, that’s the whole trap. Develop with Nf3 and g3/Bg2, then round up the d4-pawn slowly. No e3, no underpromotion trick. The habit that beats every trap on this page is the same: when a move looks like a free pawn or a free piece, stop and ask why your opponent allowed it before you take. For a systematic way to build that habit, see why you keep blundering in chess.
Is the Lasker Trap actually sound?
Be honest with yourself about what this is: the Lasker Trap is a trap first and an opening second. Against precise defence it does not win by force — it wins because the opponent does not know the one correct reply. That makes it a superb blitz and bullet weapon and a poor choice against a prepared opponent, who simply plays the refutation and emerges better. Learn it to spring it when the clock is short, and to never fall for it when it is aimed at you. If you want lines you can trust in longer games, start with a sound repertoire from the chess openings library instead.
Either way, the practical value is real. Traps like this are how club games are decided far more often than deep theory — a single unfamiliar move, an instinctive reply, and the game is effectively over. Knowing the line from both sides is worth more rating than memorising another ten moves of a mainline you rarely reach. If you want to build a repertoire that avoids nasty surprises, read how to build a chess opening repertoire.
See if this trap is costing you games
Do you keep walking into the same opening tricks — or missing the chance to punish them? Chess DNA analyses your real Chess.com and Lichess games, spots the exact openings and tactical patterns where you lose rating, and shows you the fixes. It is free, and it takes about a minute to connect your games and find your weaknesses. Then keep browsing the openings library to shore up the lines you play most.
Frequently Asked Questions
What is the Lasker Trap in chess?
In the Albin Counter-Gambit, Black underpromotes to a knight (...exd2 then ...d1=N!) winning material — one of the rare practical underpromotion traps. The trap runs 1.d4 d5 2.c4 e5 3.dxe5 d4 4.e3 Bb4+ 5.Bd2 dxe3 6.Bxb4 exf2+ 7.Ke2 fxg1=N+ 8.Rxg1 Bg4+. It is a trap Black sets against unwary White players — dangerous in fast time controls, but it has a clean answer, so a prepared opponent is never obliged to fall for it.
Is the Lasker Trap a good opening?
As a serious weapon, no — the Lasker Trap is objectively dubious against accurate defence, which is why you rarely see it in top-level classical chess. As a practical surprise weapon in blitz and bullet, it is excellent: most opponents do not know the refutation and react naturally, which is exactly what the trap punishes.
How do you beat the Lasker Trap?
The Albin’s d4-pawn is poison — do NOT play e3?? The general rule: when a move looks like a free pawn or piece, stop and work out why it was allowed before you grab it. The specific refutation is shown move by move above.
What happens if you fall for the Lasker Trap?
The line ends with 8… Bg4+ — …and this check wins White’s queen. Black emerges on top. By then White is usually lost or has dropped decisive material, which is why the trap is worth knowing from both sides.
Does the Lasker Trap work against stronger players?
Rarely. Stronger and well-prepared players recognise the pattern and play the refutation, after which the trap-setter is often worse for having invested moves in a one-shot idea. Treat it as a blitz surprise and a defensive lesson, not as a mainline you rely on against serious opposition.
