ST. PETERSBURG, Russia (AP) -- Third-seeded Martin Klizan of Slovakia advanced to the quarterfinals of the St. Petersburg Open, beating Simone Bolelli of Italy 6-3, 6-3 on Thursday.
Klizan hit five aces and never faced a break point. He will next play Ricardas Berankis of Lithuania, who advanced when eighth-seeded Jurgen Zopp of Estonia retired with a back injury after losing the first set 6-3.
Fourth-seeded Fabio Fognini also advanced, eliminating 2009 champion Serghiy Stakhovsky of Ukraine 7-6 (4), 6-4, while fellow Italian Flavio Cipolla made the final eight with a 6-2, 6-7 (5), 6-3 victory over Grega Zemlja of Slovenia.
In other second-round matches, Gimeno-Traver ousted Lukasz Kubot of Poland, 6-4, 7-6 (5), and fellow Spaniard Roberto Bautista-Agut beat Russia's Teimuraz Gabashvili 6-3, 6-4.