Poli Gambit

The Poli Gambit is one of the sharper branches of the English Defense. White's 4. f3 reinforces e4 against the bishop on b7, and Black strikes at it at once with 4...f5. After 5. exf5 Black declines to recapture with the e-pawn and plays 5...Nh6, offering a pawn so the knight can come to f5. White keeps an extra pawn but has doubled f-pawns, while Black counts on the long diagonal and the half-open f-file.