Scandinavian Defense: Portuguese Gambit, Correspondence Refutation

The Scandinavian Defense: Portuguese Gambit, Correspondence Refutation is a chess opening classified under ECO code B01 in the Semi-Open Games family, where Black responds to 1.e4 with something other than 1...e5, including the Sicilian Defense, Caro-Kann, and Pirc. It is reached after 5 moves: 1. e4 d5 2. exd5 Nf6 3. d4 Bg4 4. f3 Bf5 5. g4. The resulting position leaves black to move.