Opening family

Blackmar-Diemer Gambit Declined Lines and Variations

The Blackmar-Diemer Gambit Declined family contains 9 named lines in this opening book, spanning ECO D00. Use this page as the map, then open individual lines for exact move orders and diagrams.

Named lines

ECO coverage

D00

ECO volume

D (closed and semi-closed queen-pawn openings)

Shortest line

D00 Blackmar-Diemer Gambit Declined: Brombacher Countergambit: 1. d4 d5 2. e4 dxe4 3. Nc3 Nf6 4. f3 c5

How to study this family

White

The gambit side must turn time and activity into concrete threats; if the initiative fades, the pawn deficit matters.

Black

The defending side should return material if needed to finish development and neutralize the initiative.

Start with the shortest line, then branch to the variations that change the pawn structure or tactical target. Memorizing every branch before understanding the family plan is usually wasted work.

Main named lines

Deep theory branches

Start with the root line Drill this family