World number three Andy Murray has withdrawn from next week's inaugural $5.25 million Shanghai Masters because of a wrist injury, organisers said on Thursday.
Murray sustained the injury in Cincinnati in August and, after a medical examination on Wednesday, was advised to rest his wrist for two to three weeks, according to a statement.
"I apologise for the inconvenience that my withdrawal may cause but I trust you understand, the situation is beyond my control and I would much rather participate in the tournament than be in the current position regarding my health," Murray said in a letter to organisers.
Murray and Federer, who cited fatigue when he pulled out of the event, are among five players who have already secured their places at November's season-ending World Tour Finals in London.
World number two Rafa Nadal, also competing at the China Open in Beijing this week, heads the field at the Shanghai Masters at the Qizhong arena from Oct. 11-18.
Ivanovic to join Clijsters at Brisbane
Meanwhile, former world number one Ana Ivanovic will warm up for next year's Australian Open at the Brisbane International tournament, organisers said on Thursday.
Ivanovic, who took top spot in the rankings after winning the 2008 French Open but has now slipped to 12th, would join US Open champion Kim Clijsters and Australia's Jelena Dokic in the women's draw at the Jan. 3-10 event, tournament director Steve Ayles said.
"I am very excited to go back to Brisbane," Ivanovic said in a statement. "I really enjoyed playing there and I love competing in Australia.
"I have relatives in Melbourne so every year I look forward to it. It is one of my favourite parts of the year going Down Under."
Dokic, who spent three years in the tennis wilderness battling weight problems and self confidence issues, used the Brisbane event earlier this year as preparation for the Australian Open, where she embarked on a fairytale run to the quarter-finals.
"I loved the stadium (in Brisbane) ... and I played a really nice match (against Amelie Mauresmo), so I am looking forward to going back there and playing hopefully at that stadium for my first match," Dokic said.
"I think it will be a great way to start the year."
France's Gael Monfils and American James Blake were also confirmed for the men's draw, joining Wimbledon finalist Andy Roddick for the tournament that is one of the traditional hardcourt warm up events for the year's opening grand slam.
The Australian Open runs from Jan. 18-31.
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