Chess Opening Theory/1. f4/1...e5/2. fxe5/2...d6/3. Nf3/3...dxe5/4. Nxe5

From's Gambit
a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h
Position in Forsyth-Edwards Notation (FEN) rnbqkbnr/ppp2ppp/8/4N3/8/8/PPPPP1PP/RNBQKB1R b
Moves: 1. f4 e5 2. fxe5 d6 3. Nf3 dxe5 4. Nxe5
Parent: Bird's Opening

4. Nxe5

This move is the From's Gambit accepted. The only way to get compensation for the lost pawn and transpose back into mainline theory is 4...Bd6.

Theory table

4	5
... Bd6	Nf3 g5	+/=