[Event "?"] [Site "?"] [Round "0"] [White "Tartakower"] [Black "Sultan Khan"] [Result "0-1"] [FEN "3r2rk/1p2qppp/p4n2/2p1bP2/2P1p3/1PB5/P1QPBPRP/2K3R1 b - - 0 1"] {Useless half-open g-file White controls the half-open g-file, but can do nothing with it since there is no way of breaking the file fully open. The half-open d-file, however, which Black controls, is very important for the following reasons: 1) Black exerts an unpleasant pressure down the file, particularly through his control of support points at d4 and d3 2) This pressure can be augmented by the opening of neighboring files, the key move being ... Pb5} 1... Bd4 $1 2. Bd1 Qe5 3. Ba5 Rde8 4. Bc3 b5 5. cxb5 axb5 6. f3 e3 $1 7. Bxd4 cxd4 8. Kb1 Nd5 $17 { Black's advantage has assumed decisive proportions} 0-1