Blackmar-Diemer Gambit Declined

In the Blackmar-Diemer Gambit Declined, Black first accepts the e4-pawn with ...dxe4, but after Nc3, Nf6, and f3 does not play ...exf3. Black may instead bring out a piece with ...Nc6 or ...Bf5, support the position with ...e6 or ...c6, or counterattack the central squares with ...c5 or ...e5.

The word declined refers to the second offer, the f-pawn. This detail prevents a common misunderstanding: Black has already captured a pawn on e4 but chooses not to enter the accepted structure. The black pawn on e4 remains in the center and can become either a strong point or a target.

White often considers fxe4 to recover the pawn and build a broad center, or brings another piece into play when there is a concrete reason to preserve the tension, meaning to leave the capture on e4 unresolved. Black hopes the move f3 has weakened diagonals around White's king without granting the semi-open f-file or letting White's knight reach f3 while recapturing a pawn, as it does after 4...exf3.

Compared with the Blackmar-Diemer Accepted, the material balance and open lines are different. White's knight does not automatically reach f3 by recapture, so both sides must evaluate the actual center rather than reuse plans from the accepted branch.