BAKU, Azerbaijan (AP) Vera Zvonareva cruised into the quarterfinals of the Baku Cup on Thursday when Kristina Kucova retired with a left leg injury.

The top-seeded Russian was leading 6-0, 3-0 when Kucova quit. Although she was playing with the lower part of her left leg heavily taped, she ran well in rallies but made little headway against a more powerful opponent.

Anastasia Pavlyuchenkova defeated fellow Russian Elena Bovina 6-4, 6-0. Kateryna Bondarenko stopped fourth-seeded Ekaterina Makarova of Russia 6-1, 6-4. The Ukrainian struggled in the first half of the year, winning two matches in her opener in Auckland before a winless streak that lasted until Wimbledon in June.

Georgia's Anna Tatishvili also advanced to the quarterfinals, edging Tatia Mikadze 7-6 (4), 6-3.