What's Wrong With Andy Murray? Former World Number One a Doubt For First Grand Slam of 2018

Former world number one Andy Murray withdrew from the Brisbane International with a hip problem on Tuesday (January 2), further putting in doubt the Briton's prospects of being fit in time for the Australian Open later this month.

Murray has not played a competitive match since a Wimbledon quarter-final loss last July due to the complaint and despite coming through a one-set exhibition in Abu Dhabi last week, he was unable to train on Tuesday and announced his withdrawal.

The world number 16 and second seed had been due to play his first tournament match of the season on Thursday with a second-round encounter against American Ryan Harrison at Pat Rafter Arena.

Murray revealed that he may have to undergo surgery to his hip via an Instagram post. "I've obviously been going through a really difficult period with my hip for a long time and have sought council from a number of hip specialists," he wrote.

"Having been recommended to treat my hip conservatively since the US Open I have done everything asked of me from a rehab perspective and worked extremely hard to try get back on the court competing."

He added: "Obviously continuing rehab is one option and giving my hip more time to recover. Surgery is also an option but the chances of a successful outcome are not as I high as I would like which has made this my secondary option and my hope has been to avoid that. However this is something I may have to consider but let's hope not."

Murray is not the only former world number one whose participation at the first Grand Slam of the year is in doubt after Novak Djokovic withdrew from the Qatar Open.

The 30-year-old Serb had been scheduled to start the new season at an exhibition match in Abu Dhabi on Friday when an elbow injury flared up.

"Unfortunately, the situation with the elbow has not changed for better since yesterday," Djokovic said in a statement.

"I still feel the pain. Therefore, I will have to withdraw from ATP tournament in Doha.

"Only when I'm 100 percent ready to play, will I be able to come back. I hope it will be soon. I want to thank everyone for patience and understanding."

The 12-time grand slam winner has not played since he was forced to retire against Tomas Berdych in the quarter-finals of Wimbledon in July due to an elbow injury.

Meanwhile Japan's Kei Nishikori has pulled out of next month's Sydney International, putting his comeback on hold from a wrist injury that has kept him out of action for more than four months.

"Unfortunately Kei Nishikori has withdrawn from #SydneyTennis. We wish him well and hope to see him in Sydney in 2019," the tournament organisers posted on Twitter on Saturday.

The withdrawals of Djokovic and Nishikori raise further doubts about their participation in the Australian Open, which begins on January 15.