Top seed out at St. Petersburg Open
The 17th-ranked Italian, who was looking for his third title, struggled with his foot throughout the match and never threatened his opponent with a break.
Also, fourth-seeded Dmitry Tursunov advanced to the quarterfinals by beating Russian qualifier Konstantin Kravchuk 6-3, 6-0. Tursunov will next face Joao Sousa of Portugal, who rallied to beat Sergiy Stakhovsky of Ukraine 3-6, 6-4, 6-0.
Copyright 2013 by The Associated Press
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