Sosonko Variation
- 1.d4Nf6
- 2.c4c5
- 3.d5b5
- 4.a4
493 games
A Benko Gambit Declined line in which White plays 4. a4, undermining the b5-pawn so that Black must capture on c4 or advance to b4 at once.
Train it in TheoriaAbout the Sosonko Variation
The Sosonko Variation, 4. a4, attacks b5 a second time, so Black cannot keep the pawn there and wait to see whether White will capture. The usual reply, 4...bxc4, gives Black a doubled, weak extra pawn while White develops freely with Nc3 and e4, and it often leads to sharp, sacrificial play. 4...b4 closes the queenside and produces Benoni-like structures. The rarer 4...Qa5+ is considered the most testing. Results are roughly even.