ROME — Maria Sharapova pulled out of today's semifinals at the Italian Open with a left calf strain.

Sharapova will still take over the No. 1 spot in the world rankings Monday due to Justine Henin's retirement. She said the injury would not affect her preparations for the French Open, which begins next weekend.

"I don't think so. It's a strain," Sharapova said. "They said I need maybe three days off before they test it again."

On Friday, Serena Williams withdrew from the quarterfinals with a back problem.

Sharapova said one of the problems is that players don't want to take any risks so close to a Grand Slam. If this was the French Open, Sharapova said, she would have tried to play.

"Last year, I basically played without a shoulder, and I got to the semifinals," she said. "In a Grand Slam, you do whatever it takes, whether that's taking a few extra painkillers or whatever. But a week before a Slam to take your body to that phase, it's difficult."

The second-seeded Russian had been slated to play defending champion Jelena Jankovic.

Sharapova said she first felt the injury in the second set of her 6-7 (3), 7-5, 6-2 quarterfinal win Friday over Patty Schnyder, a match that ended near midnight.

"Last night, I had 2½ to 3 hours of treatment and it felt good, but when I woke up this morning it was really sore. I took a little jog and it didn't go well," Sharapova said. "It was really uncomfortable. I'm sorry for my fans. I hope to make it up to them soon."

In Sunday's final, Jankovic will meet either sixth-seeded Anna Chakvetadze or French qualifier Alize Cornet, who were playing later.

In the men's Rome Masters last week, also played at the Foro Italico, both semifinals ended when players withdrew with injuries. The Italian tennis federation said in a statement Saturday that it would use "all the means available to pressure international tennis authorities to alter rules to better benefit fans and promote sportsmanship."

"For the last four years, we've asked for a rule that would require the losing semifinalists to stay in town in case somebody pulls out of the final, but the players have refused," tournament director Sergio Palmieri said. "There are pros and cons of being a warmup tournament for a Grand Slam. We get the best players, but then this happens sometimes."

Sharapova had a flight booked to Paris later Saturday.

"I hope in two days I'll be able to be on the court and be normal," she said.