Sharapova struggles past Krajicek

Sharapova could lose her world number one ranking in California

Top seed Maria Sharapova was given a thorough workout as she began the defence of her Pacific Life Open crown in Indian Wells, California.

The world number one, who had a bye in the opening round, needed an hour and 44 minutes to see off Dutch player Michaella Krajicek 7-6 (7-5) 6-4.

Sharapova, 19, hit 50 unforced errors and served 10 double faults.

Ex-champion Martina Hingis reached the third round more easily, breezing past Denmark's Caroline Wozniacki 6-1 6-3.

It was a rusty display from Sharapova, who has been out of action for over a month because of a hamstring injury.

"I'm just happy to get through the match. I've just got to keep improving," she said.

Sharapova will now meet France's Nathalie Dechy who upset Italian 31st seed Flavia Pennetta 6-7 (3-7) 6-4 6-2.

Another former champion to progress was Daniela Hantuchova, who came through 6-2 2-6 6-1 against Kaia Kanepi of Estonia.

Seventh seed Jelena Jankovic beat American Shenay Perry 6-1 6-3 while eighth seed Anna Chakvetadze overcame Croatia's Mirjana Lucic 6-2 7-5.

Three-time former French Open champion Gustavo Kuerten was beaten in the first round of the Indian Wells Masters Series.

The Brazilian, who was the runner-up in 2003 but who has struggled with a hip injury over the last couple of seasons, lost 7-6 (7-5) 6-2 to Argentine Juan Martin del Potro.

The 32 seeded players in the men's draw all received first-round byes so none were in action on Friday.