Maria Sharapova out of U.S. Open

(CNN) -- Maria Sharapova has been forced out of the U.S. Open with a right shoulder injury, continuing a turbulent few months for the four-time grand slam winner.

The world No. 3 is suffering from bursitis, which occurs when a small, fluid-filled sac forms under the skin.

"I have done everything I could since Wimbledon to get myself ready but it just wasn't enough time," Sharapova said in a statement released on her website.

"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 favorite tournaments, but I know it's the right one that will get me back on the courts soon.

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"I plan on taking the next few weeks off, receiving proper treatment and rehabilitation. I will miss being part of the US Open, but can't wait for next year."

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After losing to Portuguese qualifier Michelle Larcher De Brito in the second round of Wimbledon in June, the Russian ended her three-year partnership with coach Thomas Hogstedt.

She then hired legendary eight-time grand slam winner Jimmy Connors as his replacement, but that was ended after just one match, her second-round defeat to American starlet Sloane Stephens at the Western and Southern Open in Cincinnati.

The 2006 U.S. Open champion had reportedly agreed to have her father coach her throughout the year's final grand slam.

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Sharapova grabbed the headlines earlier this week amid suggestions she was set to change her name to "Sugarpova" for the duration of tournament, a marketing stunt designed to promote her candy range.

Her representatives, however, told CNN that it would be "too complicated."

In Sharapova's absence Poland's Agnieszka Radwanska will be instated as the third seed for Thursday's draw.

Home fans suffered a blow with the news that American Mardy Fish has withdrawn from tournament as he continues to struggle with ongoing health issues.

The former world No. 7 has been battling a heart condition which first came to light in May 2012 and required him to have surgery to correct faulty electrical connections within his heart.

Fish has already missed the Australian and French Opens and Wimbledon this year.

Earlier this week he was forced to withdraw from his match with Jarkko Nieminen at the Winston-Salem Open.

"Friends, unfortunately my health won't allow me to compete this year at the US Open. Thank you for all your support," the 31-year-old announced on his official Twitter account.

Fish reached the fourth round at Flushing Meadows in each of the last three years and was a quarterfinalist in 2008.