STANFORD -- American Varvara Lepchenko upset second-seeded Agnieszka Radwanska 6-3, 3-6, 6-4 in a grueling second round match at the Bank of the West Classic Wednesday.
The 28-year-old Lepchenko, unseeded and ranked 59th in the world, had never beaten Radwanska, a Bank of the West finalist last year and the World Tennis Association's fifth-ranked player, in five prior meetings.
Lepchenko, who was born in Uzbekistan but became a U.S. citizen in 2007, broke Radwanska in the fifth game of the decisive third set, but Radwanska immediately broke back. But leading 5-4, Lepchenko used powerful forehand winners to break the standout from Poland once again and take the match.
Radwanska's defeat leaves just one seeded player on one side of the Bank of the West bracket, third-seeded Angelique Kerber of Germany. Sixth-seeded and defending champion Dominika Cibulkova was upset in the opening round, as was seventh-seeded Carla Suarez-Navarro.
Top-seeded and world No. 1 Serena Williams, who drew a bye in the opening round, was scheduled to play her first match Wednesday night against the Czech Republic's Karilina Pliskova.
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