Indian Defense: Budapest Gambit Accepted, Main Line, Alekhine Variation, Tartakower Defense
ECO A52
Move order
1. d4 Nf6 2. c4 e5 3. dxe5 Ng4 4. e4 d6
Ideas
ECO A covers irregular and flank openings—systems that skip the main e4/d4 fight early. White builds a pawn center and keeps the position more closed than after 1. e4. This entry tracks a longer branch in the opening tree. Use the diagram and SAN list to recognize the tabiya, then try the line against Maia to explore typical plans in practice.