Sicilian Defense: Open, Scheveningen, Classical, Paulsen Variation

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 e6 6.Be2 a6 7.O-O Qc7 8.f4 Nc6 9.Be3 Be7 10.Qe1 O-O 11.Kh1 Nxd4 12.Bxd4 b5 13.a3 Bb7