Lasker Trap
D08 · Played as black · Intermediate · Traps & Tricks
An underpromotion to a knight — on move seven
The main line
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+
Strategic ideas
- Play the Albin Counter-Gambit and push …d4 as a permanent thorn
- Check on b4 so that White's natural Bxb4 hangs everything
- Push the pawn to f2 and promote to a knight with check — not a queen
- Win the queen with the tiniest piece on the board
- Set the earliest underpromotion trap in the whole opening book
Key themes
- Tactics — The entire line hangs on one detail: a knight promotion gives check and a queen promotion doesn't
- Counterattack — Black gives up a pawn on move two and never stops making threats
- Dynamic — The d4-pawn is a permanent nuisance and the whole position runs on concrete tactics
Typical plans
The Albin Counter-Gambit is already cheeky — Black offers the e5-pawn on move two to plant a pawn on d4. The Lasker Trap is what happens when White develops naturally. After 6.Bxb4?? exf2+, Black's pawn reaches f2 with check, and then comes the famous move: promoting to a knight, with check, forking the king and the queen. A queen promotion would just be met by Rxg1. It's the earliest underpromotion in serious opening theory and it never stops being delightful.
Move by move
- d4 — White claims the centre.
- d5 — Black meets it symmetrically.
- c4 — White offers the Queen's Gambit.
- e5 — Black plays the Albin Counter-Gambit, offering a pawn to open lines and plant a pawn on d4.
- dxe5 — White takes.
- d4 — Black pushes past. This pawn on d4 is the whole idea — it cramps White and can't easily be removed.
- e3 — White challenges the pawn immediately. This is already slightly careless.
- Bb4+ — Black checks. The bishop can't be taken without consequences, and the check gains a tempo.
- Bd2 — White blocks with the bishop, which looks entirely natural.
- dxe3 — Black takes on e3, opening the f2-pawn's path.
- Bxb4 — White takes the bishop. This is the losing move — fxe3 was necessary. Now Black's e3-pawn has a clear run at f2.
- exf2+ — Black takes with check. The pawn is one square from promotion and White's king must move.
- Ke2 — White's king steps to e2, the only square that doesn't lose immediately.
- fxg1=N+ — Black promotes to a knight — and it's the check that matters. A new queen on g1 wouldn't give check at all, and White would simply reply Qxd8+ and win. The knight checks, so White has no time for anything else.
- Rxg1 — White must deal with the check and takes the knight.
- Bg4+ — Black skewers king and queen. The king has to step aside, and the queen on d1 falls next move. A pawn walked to f2, turned into a knight, and cost White the queen — all before move nine.