Updated

Rafael Nadal breezed past American qualifier Ryan Sweeting 6-3, 6-1 in a third-round match as the second week of the BNP Paribas Open began Monday.

Nadal improved to 28-4 in his career at Indian Wells, where he's won twice. The world's top-ranked men's player has lost six games in his first two matches while showing no lingering effects from his recent left thigh injury.

Women's top seed Caroline Wozniacki of Denmark advanced with a 6-1, 6-3 victory against Maria Jose Martinez Sanchez of Spain that took just over an hour. Wozniacki has improved her results in each of her first four years playing at Indian Wells, where she was runner-up to champion Jelena Jankovic last year.

Other women's winners were No. 8 Victoria Azarenka, No. 9 Agnieszka Radwanska of Poland, No. 16 Maria Sharapova and No. 22 Alisa Kleybanova of Russia.

Sharapova beat 20th-seeded Aravene Rezai of France, 6-2, 6-2 as the Russian star returns to the WTA Tour after a five-week absence because of illness.

"I started like I didn't have my cup of coffee or something, didn't have my peeps around, so that was disappointing," Sharapova said. "When she's on, she can be one of the toughest players to play against. She had a lot of errors. I returned a lot better, and served a lot better in the second set."

There were two upsets on the men's side: fourth-seeded Robin Soderling of Sweden and No. 11 seed Nicolas Almagro of Spain both lost.

Soderling fell to No. 32 seed Philipp Kohlschreiber of Germany, 7-6 (8), 6-4 after holding five set points in the tiebreaker; while 23rd-seeded Albert Montanes of Spain took out Almagro 4-6, 6-2, 6-4.

Soderling was bothered by a left foot injury that first occurred during Sweden's victory over Russia in Davis Cup play nearly 10 days ago.

"I lost the match when I decided to go on court," he said. "I shouldn't have done that. It's pretty stupid to play."

Soderling, who was in bed for five days with a fever before the tournament began, had yet to have his foot examined by a doctor. He is scheduled to play at Key Biscayne, Fla., next week.

"Hopefully, they won't find anything bad," he said. "The more I play on the foot, the worse it gets."

American qualifier Donald Young's run ended with a 6-0, 6-4 loss to 25th-seeded Tommy Robredo of Spain, two days after Young upset fifth-ranked Andy Murray.

Juan Martin del Potro of Argentina, the 2009 U.S. Open champion, defeated 20th-seeded Alexandr Dolgopolov of Ukraine 7-6 (3), 6-3.