The Rousseau Gambit has a small published record. These games show its practical character: playable against an unprepared opponent, but vulnerable when White opens the center accurately.

10.1 Morphy versus Rousseau, 1849

Morphy declined the pawn with 4.d3. The game was decided before the famous combination: after 9…c6, White already had a large edge. 10.Nce4 was not the engine’s best move, but it posed the hardest practical question; 10…fxe4 doubled White’s advantage.

10.2 Other historical games

Morphy won this game blindfold in an eight-board simultaneous display. Its shape is the 4.d4 problem: queens come off early, Black’s king remains in the center, and White converts the open lines.

10.3 Modern play

Modern practical play reaches the doubled c-pawn structure after 4.exf5 e4 5.Nd4 Nf6 6.Nxc6 dxc6. In this game Black’s bishop pair and the open lines mattered more than White’s temporary extra pawn.

10.4 Master practice

Against prepared players, 4.d4 and 4.d3 replace 4.exf5. The opening is not refuted by force, but it does not survive accurate, unhurried play as reliably as it does fast online games.