Final position — White is winning
Petrov's Defence: Wins a Piece
White wins in 10 moves with a decisive material gain. (Gross - Lien, San Francisco 1974)
The moves
| 1. | e4 | e5 |
| 2. | Nf3 | Nf6 |
| 3. | Nc3 | d5 |
| 4. | exd5 | Bg4 |
| 5. | Be2 | Bd6 |
| 6. | d4 | exd4 |
| 7. | Qxd4 | O-O |
| 8. | Bg5 | h6 |
| 9. | Bxf6 | Qxf6 |
| 10. | Qxg4 |
How the Petrov's Defence: Wins a Piece works
The Petrov's Defence: Wins a Piece is a classic chess opening trap arising from the Petrov's defence. In this line White wins decisive material by move 10, punishing a natural-looking but losing idea from Black.
The full sequence runs 1.e4 e5 2.Nf3 Nf6 3.Nc3 d5 4.exd5 Bg4 5.Be2 Bd6 6.d4 exd4 7.Qxd4 O-O 8.Bg5 h6 9.Bxf6 Qxf6 10.Qxg4. Each move looks reasonable, which is exactly why the trap is so effective over the board — Black walks into it while trying to play "normal" developing moves.
This pattern is well known from master and correspondence play (Gross - Lien, San Francisco 1974). Recognising it early lets you either spring it as White or sidestep it as Black.
Practice this trap move-by-move
Open the Petrov's Defence: Wins a Piece in the Trapsterapp to play it out on a live board, drill it in practice mode, and learn how to avoid it when it's set for you — along with the full library of chess traps and gambits, fully offline.