Three-time Grand Slam champion Maria Sharapova pulled out of this week's tennis tournament in Miami because she hasn't fully recovered from a shoulder injury.
"I am still not ready to play seven consecutive matches and will have to withdraw from the Sony Ericsson Open, which is one of my favorite tournaments," Sharapova said on her Web site.
She hasn't played a singles match in more than seven months, and had an operation on the shoulder in October. The Russian, a former top-ranked player who won Wimbledon at the age of 17, has slipped to No. 30 in the rankings after her injury prevented her from playing in the Beijing Olympics, the U.S. Open and the Australian Open.
The 21-year-old, the biggest money-earner in women's tennis, lost a doubles match on her return to the tour ten days ago in Indian Wells, California. She told reporters after that match she had stopped setting herself a timeline for her return to the singles competition.
Sharapova, who became Sony Ericsson's first "global brand ambassador" in January last year, will travel to the Miami tournament, which starts on March 25, to sign autographs for fans, she said on her Web site.