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ECO D04

ECO D00–D99 — Closed and Semi-Closed Games: 1.d4 d5 queen's pawn openings and the Grünfeld Defense.

3 named opening lines are classified under ECO code D04.

Queen's Pawn Game: Colle System — 1.d4 d5 2.Nf3 Nf6 3.e3
Queen's Pawn Game: Colle System, Anti-Colle — 1.d4 d5 2.Nf3 Nf6 3.e3 Bf5
Queen's Pawn Game: Colle System, Grünfeld Formation — 1.d4 d5 2.Nf3 Nf6 3.e3 g6 4.Bd3 Bg7