Vera Zvonareva has reached the fourth round of the US Open after a straight-sets victory over Anabel Medina Garrigues.
The second seed took two hours to beat her resilient Spanish opponent, winning the match 6-4 7-5.
The Russian will face either Sabine Lisicki or Irina Falconi in the next stage.
Zvonareva was a losing finalist in last year's tournament.