Former world number one Maria Sharapova's [Images] preparations for the Australian Open [Images] have suffered a setback with her withdrawal from the Australian women's hard court tournament on the Gold Coast because of a shoulder injury.

The 18-year-old Russian said in a statement on Saturday the shoulder strain had forced her to withdraw from the January 2-7 event on the Gold Coast and she was still not sure if she would be fit enough to play the Australian Open, the year's opening Grand Slam in Melbourne, which begins on January 16.

"I am very disappointed to have to withdraw because my right shoulder is not yet ready to allow me to compete at the tour level," the world number four said.

"The number one priority for me at this time is getting 100 per cent healthy to compete again," she added.

Sharapova reached the semi-finals at three of the four grand slam tournaments in 2005 and won three WTA tour titles.

Former world number one Martina Hingis [Images] is returning from retirement at the Gold Coast tournament.

The Swiss will also play the Sydney tournament before the Australian Open.

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