Britain's Andy Murray has had hip surgery in Melbourne and says he hopes to be playing again in time for this summer's grass-court season.
The former world number one, 30, has not played a competitive match since he was knocked out of Wimbledon in July.
The ongoing problem forced the Scot to pull out of the Australian Open,which begins on 15 January.
"I'm not finished playing tennis yet. I'm going to be competing at the highest level again," he said.
"I'm very optimistic about the future - the surgeon is very happy about how it went."
Murray, a three-time Grand Slam champion, believes if he can return to 95% of his best, that will be enough for him to compete again at the top level.
He hopes he will be hitting balls on court again after seven or eight weeks, and has been given 14 weeks as a guide for a return from this kind of surgery.
But Murray, who has fallen to 19th in the world, said he is not "interested in coming back for a specific tournament".
"My plan is to be back playing around the grass-court season - potentially before then - but I'm certainly not going to rush anything," said Murray, speaking from his hospital bed in a telephone conference call to a group of British journalists.
"I want to know when I come back that I'm ready."
He was operated on by Dr John O'Donnell at the St Vincent Hospital in Melbourne on Monday.
Murray posted a photo from hospital on Instagram and said: "Feeling really positive and looking forward to starting rehab."