ECO D51
5 named openings and variations are classified as D51. ECO (Encyclopaedia of Chess Openings) codes group openings from A00 to E99 by their opening moves.
- Queen's Gambit Declined: Alekhine VariationD511. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. Nf3 c6 6. e4
- Queen's Gambit Declined: Capablanca Variation, Anti-Cambridge Springs VariationD511. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. e3 c6 6. a3
- Queen's Gambit Declined: Manhattan VariationD511. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. e3 Bb4
- Queen's Gambit Declined: Modern Variation, Knight DefenseD511. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7
- Queen's Gambit Declined: Rochlin VariationD511. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. Nf3 c6 6. Rc1 Qa5 7. Bd2