von Popiel Gambit

The von Popiel Gambit is the line 1. d4 d5 2. e4 dxe4 3. Nc3 Nf6 4. Bg5, introduced by Ignatz von Popiel in 1889, well before Emil Diemer made 4. f3 the standard follow-up. Rather than striking at e4 with a pawn, White targets the knight that defends it. A later Bxf6 would remove that defender and threaten to recover the gambit pawn with Nxe4, while the d-pawn and half-open lines keep White's development fluid.

The most common answer is 4...Bf5, which adds a second guard to e4. A known trap follows 5. Qe2 Qxd4?, when 6. Qb5+ forks king, bishop and the b-pawn. The Zilbermints Variation, 5. Bxf6 exf6 6. g4 Bg6 7. Qe2 Bb4 8. Qb5+, gives up the bishop pair and chases Black's light-squared bishop with kingside pawns. Other replies include 4...e6, which transposes to the Burn Variation of the French Defense, and 4...Nc6. The engine prefers Black slightly, but in online play White scores a little better than Black, and decisive results are the norm.