411 REFERENCE · Wikibooks
Chess Opening Theory/1. e4/1...c5/2. Nf3/2...e6/3. d4/3...cxd4/4. Nxd4/4...Nc6/5. Nb5/5...d6/6. c4/6...Nf6
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Szén variation B45 Szén variation
6...Nf6
6...Nf6 develops while threatening White's e4 pawn.
White can defend with 7. N1c3, developing their second knight and intending their other knight to retreat to a3, or 7. N5c3, leaving their knight on b1 undeveloped for now.
Theory table
References
See also
Sicilian Defence
The Sicilian Taimanov Pavlidis Antonios Quality Chess UK 2019 978 1 78483-058 8 Glasgow