Spielmann Variation

The Spielmann Variation, 4. Qb3, is named after Rudolf Spielmann, who used it at Carlsbad 1929. Like the Classical Variation 4. Qc2, the queen move defends the c3-knight so that ...Bxc3 can be met by a queen recapture, sparing White doubled c-pawns, and it also attacks the bishop on b4. The drawback is that from b3 the queen has no say over e4, which Black can occupy freely. Masters played it in the early 1930s before 4. Qc2 displaced it, and despite occasional revivals by Akopian, Malaniuk and Piket it remains a sideline. ECO assigns it E22 and E23.

The main replies are 4...Bxc3+, giving up the bishop pair at once, and 4...c5, striking at d4. After 4...c5 5. dxc5 Nc6, the Romanovsky Gambit, Black develops rather than regaining the pawn immediately; 6. Nf3 Ne4 then uses the unguarded square to press on c3. On 7. Bd2, the Carlsbad Variation 7...Nxd2 trades knight for bishop, while the Stahlberg Variation 7...Nxc5 recovers the pawn with gain of time against the queen. Engine assessment is level and online results are nearly even.