The variation 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e5 6. Ndb5 d6 7. Bg5 a6 8. Na3 b5 9. Bxf6 gxf6 10. Nd5 Bg7 11. Bd3 Ne7 12. Nxe7 Qxe7 13. O-O f5 14. c4 O-O is one of the tabiyas of the Pelikan/Sveshnikov variation. But one of the taboos of this variation for White is never to snatch the forbidden fruit in this variation with 15. cxb5. This move is not considered in Gufeld, Modern Chess Openings, Nunn's Chess Openings, or Sveshnikov's own work on this variation as it is just assumed that White allows dangerous counterplay in this variation.
However, the machines love this move as it wins a pawn for White and they do not have nerves like humans do. But even the machines can be wrong sometimes; in this variation, White captures the pawn only to allow dangerous counterplay along the long Black diagonal along with a central pawn roller. However, White, Tatev Abrahamyan, lived to tell about it after her opponent, Alisa Melekhina, failed to adhere to Nimzovitch's basic principle never to omit to block a passed pawn in the recent US Women's Championship. White won the game, but Black missed some key chances at counterplay.
On her 21st turn, Black could have played 21...Ra6!?. That would have created a Rook lift over to the King Side to either g6 or h6 and target the King side since the pawn on e4 ensures that there is no defending Knight present.
But Black's losing move came on move 23 when she forgot to block the passer with 23...Bd7! and instead was too impatient and played 23...f3? White won a pawn with the cold-blooded 24. gxf3! thanks to the pin on the Queen and thanks to her advanced passer that Black failed to block, was able to liquidate into a won ending with 24...Bh3 25. Kh1 Qf4 26. d7 Red8 27. Qxe4! All of a sudden, an attack that had looked so promising was smothered out of the blue and Black gave up after 63 moves in a long hopeless ending a pawn down.
Had Black shown more patience with 23...Bd7, a different struggle would have developed. After 24. Rd5! (best, to stop ...Qg5) Qf6 25. Nd4, now Black can play her intended 25...f3! and break up White's King Side with 26. Qf1 (forced) fxg2. White will have difficulties as she will have trouble trying for a win without exposing her King to checks.
Tatev Abrahamyan finished the tournament with 4 wins and 4 losses with one draw. All of the decisive games she played were won by White.