CARLSBAD, Calif. (AP) _ Ai Sugiyama took advantage of numerous unforced errors and played consistently Thursday to upset second-seeded Svetlana Kuznetsova in the third round of the Acura Classic.
Kuznetsova, ranked fourth in the world, committed 69 unforced errors, including 56 over the final two sets in her first match since losing in the Wimbledon quarterfinals more than a month ago. Sugiyama won 2-6, 6-4, 6-3.
"I think I was playing good tennis at times,'' said U.S. Open champion Kuznetsova. "I just didn't keep my level at the top.''
Kuznetsova became the last of six seeded Russian players to be eliminated from the $1.3 million event, including three Thursday. All three of the top playing seeds were Russian, Kuznetsova, No. 3 Elena Dementieva and fourth-seeded Nadia Petrova, and all are gone before the quarterfinals.
Top-seeded American Lindsay Davenport withdrew with a strained back on Sunday, the day before the tournament began.
Russia's only remaining player from the 11 who entered the event is unseeded Anna Chakvetadze, who defeated No. 9 seed and countrywoman Elena Likhovtseva 6-3, 6-1 Thursday.
No. 16 Dinara Safina was the third seeded Russian to lose Thursday, falling 7-6 (2), 6-0 to Shuai Peng of China. On Wednesday, Peng eliminated Dementieva, the world's sixth-ranked player.
No. 5 Patty Schnyder is the highest seeded player left after her 6-7 (1), 6-1, 6-4 win over No. 17 Francesca Schiavone of Italy. Schnyder, a two-time winner this season, raised her season record to 42-14, moving past Maria Sharapova (41-7) for the most wins on the WTA Tour.
Tenth-ranked Kim Clijsters of Belgium is the only top-10 player remaining in the draw. Clijsters, seeded seventh, moved into the quarterfinals with a 6-1, 6-3 win over No. 11 Jelena Jankovic of Serbia and Montenegro. Clijsters, who won the Bank of the West Classic Sunday, is shooting for her fifth title this seaso.
Sixth-seeded Mary Pierce defeated fellow Frenchwoman and Davis Cup teammate Nathalie Dechy, 7-5, 6-3 in the featured night match. Pierce, the French Open runner-up and two-time Grand Slam champion, is undefeated in four career matches against the 10th-seeded Dechy.
Sesil Karatantcheva of Bulgaria advanced to her third quarterfinal this season with a 6-1, 6-2 win over Mashona Washington. Karatantcheva, who will turn 16 Monday, eliminated the last American in the field.
It's only the second time in the tournament's 22-year history that no Americans qualified for the quarterfinals, and the first time since 1996.
Kuznetsova breezed through the first set before Sugiyama took a close second set. They were on serve until Sugiyama broke through in the fifth game to take a 3-2 lead and won her service game at love for a 4-2 advantage. Sugiyama closed out on her first match point when Kuznetsova hit a backhand into the net.
"I gave her a chance to get into the match in the second (set),'' Kuznetsova said. "And in the third, it was much more difficult to beat her. I wasn't concentrating enough.''
Sugiyama acknowledged that Kuznetsova wasn't at the top of her game.
"I've seen her play better than today,'' Sugiyama said. "She was thinking smart at the beginning. But maybe the concentration wasn't great today, up and down. I tried to just play every point and focus.''
Japan's Akiko Morigami moved into the quarterfinals with a 6-2, 4-6, 6-4 victory over qualifier Sania Mirza of India. Mirza upset Petrova on Wednesday.