Petrov Defense Trap
The Petrov Defense trap: copying White with 3...Nxe4? runs into 4.Qe2, and moving the knight away loses the queen to a discovered check.
In the Petrov Black mirrors White's moves, but the mirror breaks on move three. Taking on e4 at once puts both knights on the open e-file with the black king behind them. Many club players take the pawn by reflex.
How the Petrov Defense Trap works
Click a card to see it on the board, then play the punishment yourself.
How often does it work?
Counted in real rated Lichess games, not estimated.
| Rating | Reached the position | Played 4...Nf6? | Fall rate |
|---|---|---|---|
| 1200–1400 | 816 games | 80 | 10% |
| 1500–1700 | 382 games | 23 | 6% |
| 1900–2100 | 181 games | 5 | 3% |
Sample: up to 1,000,000 rated Lichess games per rating band (May 2024), same move order only.
Among players rated 1800 and higher, 4...Nf6? was played in 139 of the games our puzzles are drawn from. Strong players fall for it too.
How to avoid the Petrov Defense Trap
What Black should play instead.
Other versions of the trap
The same idea from a different move order.
Now spot it in a real game
Knowing a trap by name is not the same as seeing it at the board. Solve positions from real games until the pattern fires by itself.
Petrov Defense Trap
Getting there…After 4.Qe2 the knight on e4 is attacked, and if it moves, the white knight moves too. 4...Nf6 5.Nc6+ is a discovered check from the queen that also attacks the black queen. Black loses her for a knight.