"Maria has informed us that she will be unable to compete at the US Open this year due to a right shoulder bursitis and has withdrawn from the tournament," said David Brewer, Tournament Director of the US Open. "We wish her a speedy recovery and look forward to her return to New York next year."
"Maria Sharapova's withdrawal from the 2013 US Open results in Agnieszka Radwanska becoming the No.3 seed in women's singles and the seeded players below each move up one position," said Brian Earley, Tournament Referee of the US Open. "Anastasia Pavlyuchenkova becomes the No.32 seed."
Sharapova, a four-time Grand Slam champion - including capturing the US Open in 2006 - had been sidelined much of the summer with a hip injury, and will sit out the biggest one of the summer now.
This is just the third time Sharapova has ever had to miss a Grand Slam tournament, the other two instances coming at the 2008 US Open and 2009 Australian Open, which fell in a nine-month period the Russian had to sit out due to a right shoulder injury, coincidentally (August 2008 to May 2009).
"Withdrawing from the US Open has been a really tough decision to make," Sharapova said later on in the day in a statement on her official Facebook page. "I have done everything I could since Wimbledon to get myself ready but it just wasn't enough time. I have done many tests, received several opinions and it all comes down to taking the proper amount of time to heal my shoulder injury properly."