Budapest Gambit Accepted, Fajarowicz Defense

The Fajarowicz Defense, sometimes called the Fajarowicz Gambit, puts the knight on e4 rather than g4. Black stops trying to win back e5 at once and develops quickly, relying on tactics. Typical ideas include an ill-timed ...Bb4+, ...Qf6 hitting b2 and f2 together, and, after White plays e3, a combined attack on d3 with ...Nc5, ...Bf5 and ...Nb4. The line traces back to Leipzig players, and its first significant game was H. Steiner versus Fajarowicz at Wiesbaden in 1928. Engines give White a clear advantage, yet Black scores slightly better than White in Lichess games.

4. Nf3 is the most frequent reply. It develops and covers d2, and after 4...Bb4+ 5. Nbd2 Nc6 6. a3 Nxd2 7. Nxd2 Bf8 Black struggles to justify the pawn. The Bonsdorf Variation, 4. a3, rules out both ...Bb4+ and ...Nb4 and prepares Qc2. Lalic and de Firmian both rate it as White's best, and Lalic answers it with 4...b6. The Steiner Variation, 4. Qc2, attacks the knight immediately and is usually met by 4...Bb4+ followed by ...d5.