Summary Davis notched her first win against a top-10 player.
INDIAN WELLS, United States (AFP) - Victoria Azarenka s fighting spirit just wasn t enough on Friday as the injured third seed was sent packing from Indian Wells by 66th-ranked American Lauren Davis.
With the world number four from Belarus hobbled by a painful left foot, the 20-year-old Davis triumphed 6-0, 7-6 (7/2).
"Basically all I had was my fighting spirit today," said Azarenka, who was playing her first tournament since a quarter-final exit at the Australian Open.
She had returned to the practice court less than a week earlier, after three weeks in a protective boot.
"I wanted to give my best shot," Azarenka said. "Obviously it was maybe a little bit too early. But I gave a fight. I m pretty proud of whatever I did today.
"You also have to give her credit," Azarenka said of Davis. "In this situation it s not easy to close the match and she s done it."
Davis notched her first win against a top-10 player. She booked a third-round meeting with compatriot Varvara Lepchenko, who upset 29th-seeded Daniela Hantuchova, the 2002 and 2007 champion, 6-3, 6-2 in 84 minutes.
Second-seeded Agnieszka Radwanska reached the third round of the combined WTA and ATP Masters hard court tournament with a straight-sets win over British qualifier Heather Watson.
Poland s Radwanska, ranked number three in the world, needed one hour and 24 minutes to get past the 134th-ranked Watson 6-4, 6-3. She next faces either Russian Elena Vesnina or Germany s Annika Beck.
"The first match is always challenging," said Radwanska, who like all 32 men s and women s seeds in the $12 million tournament enjoyed a first-round bye.
In a match littered with 12 service breaks -- including seven in the second set -- she held serve to finish out the match, giving herself another reason to celebrate a day after her 25th birthday.
"I m just happy I got through and finally won my serve the last game," she said.
Radwanska next faces Germany s Annika Beck, who beat 30th-seeded Russian Elena Vesnina 6-2, 3-6, 6-3.
- Blockbuster Saturday -
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Women s top seed Li Na, the Australian Open champion from China, will open her campaign against compatriot Zheng Jie on a blockbuster Saturday that will also see defending women s champion Maria Sharapova, seeded fourth, take on Germany s Julia Goerges.
Men s top seed and defending champion Rafael Nadal, third-seeded Australian Open champion Stanislas Wawrinka, fifth-seeded Andy Murray and seventh-seeded Roger Federer will also battle for third-round places.
Nadal faces Czech veteran Radek Stepanek, Wawrinka faces a tough second-round opener against big-serving Croatian Ivo Karlovic, Murray tackles Czech Lukas Rosol and Federer faces French qualifier Paul-Henri Mathieu.
Elsewhere on Friday, seventh-seeded Jelena Jankovic of Serbia, ninth seed Sara Errani of Italy and 10th-seeded Dane Caroline Wozniacki also moved into the third round.
Jankovic, the 2010 Indian Wells champion, defeated Austrian Yvonne Meusburger 6-3, 6-1.
Errani needed just 71 minutes to complete a 6-1, 6-1 victory over qualifier Sharon Fichman, while Wozniacki, the 2011 champion, beat Serbia s Bojana Jovanovski 6-1, 6-3.
In men s first-round matches, Romanian Victor Hanescu lined up a clash with second-seeded Novak Djokovic with a 7-5, 3-6, 6-4 victory over French qualifier Stephane Robert.
