Maria Sharapova has admitted it was "a really tough decision" to pull out of the US Open with a shoulder injury.
Sharapova had been seeded three at Flushing Meadows but inflammation in her right shoulder has forced her to withdraw.
The four-time grand slam champion released a statement on her Facebook page explaining: "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.
"It's certainly not an easy decision to make ahead of one of my favourite tournaments, but I know it's the right one that will get me back on the courts soon.
"I plan on taking the next few weeks off, receiving proper treatment and rehabilitation."
Sharapova, who won the title in 2006, will be replaced as third seed by Agnieszka Radwanska.
Tournament director David Brewer said: "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has informed us that she will be unable to compete at the US Open this year due to a right shoulder bursitis and has withdrawn from the tournament.
"We wish her a speedy recovery and look forward to her return to New York next year."
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