Final position — White is winning
English Opening: Opening Trap (Knopp–Koebele)
White wins in 6 moves with a decisive material gain. (Knopp - Koebele, 1992)
The moves
| 1. | c4 | Nf6 |
| 2. | Nc3 | d5 |
| 3. | d4 | Bf5 |
| 4. | Qb3 | Nc6 |
| 5. | cxd5 | Nxd4 |
| 6. | Qa4+ |
How the English Opening: Opening Trap (Knopp–Koebele) works
The English Opening: Opening Trap (Knopp–Koebele) is a classic chess opening trap arising from the English Opening. In this line White wins decisive material by move 6, punishing a natural-looking but losing idea from Black.
The full sequence runs 1.c4 Nf6 2.Nc3 d5 3.d4 Bf5 4.Qb3 Nc6 5.cxd5 Nxd4 6.Qa4+. 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 (Knopp - Koebele, 1992). Recognising it early lets you either spring it as White or sidestep it as Black.
Practice this trap move-by-move
Open the English Opening: Opening Trap (Knopp–Koebele) 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.