The Monticelli Trap is a variation of the Bogo-Indian Defense, catalogued as ECO E11. The line runs 1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Bb7 5. Bg2 Bb4+ 6. Bd2 Bxd2+ 7. Qxd2 O-O 8. Nc3 Ne4 9. Qc2 Nxc3 10. Ng5, reaching the position shown below after 19 half-moves.
White holds the centre with pawns on d4. Development is level at four minor pieces each, and Black is up three points of material. It is Black to move after ten moves. Black has castled while White’s king is still uncommitted.
On the Bogo-Indian Defense generally: ECO E11. A chess opening with 17 known variations.
You can play through this variation move by move in your browser — Learn mode walks the line with an explanation at each step, and Drill mode replays it from memory so you find out whether you actually know it. No account is required.
See all 12 Bogo-Indian Defense variations →
The Monticelli Trap goes 1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Bb7 5. Bg2 Bb4+ 6. Bd2 Bxd2+ 7. Qxd2 O-O 8. Nc3 Ne4 9. Qc2 Nxc3 10. Ng5. It is a variation of the Bogo-Indian Defense and is catalogued as ECO E11.
The Monticelli Trap is ECO E11. ECO codes group openings by their move order, so nearby codes cover closely related lines of the Bogo-Indian Defense.
Stockfish evaluates the position after 1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Bb7 5. Bg2 Bb4+ 6. Bd2 Bxd2+ 7. Qxd2 O-O 8. Nc3 Ne4 9. Qc2 Nxc3 10. Ng5 at +0.41 at depth 18, which is a slight pull for White, within normal opening margins. Engine evaluation is only a starting point — at club level the practical value of a line is mostly about whether you know its plans better than your opponent does.
White holds the centre with pawns on d4. Development is level at four minor pieces each, and Black is up three points of material. It is Black to move. Black has castled while White’s king is still uncommitted.