Andy Murray has revealed he intends to end his career after Wimbledon - but injury may mean he cannot play beyond the Australian Open next week.
The 31-year-old Briton played only 12 matches last year and, returning to the Brisbane International last week, he won his opening match but lost in the second round, visibly limping at times.
He said he plans to play his opening match at the Australian Open on Monday against world number 22 Roberto Bautista Agut.
However, when asked if this might be his last tournament, he said: "Yes I think there's a chance of that for sure because I'm not sure I'm able to play through the pain for another four or five months."
Murray wiped away tears during a 10-minute press conference and at one point was so overcome by emotion that he walked out.
Minutes later he returned to talk about how the sport that dominated his life had left him with a hip injury so bad he sometimes struggled to put on his shoes and socks.
He said he had a "severely damaged" hip and had been playing with the pain "for a number of years".
Fighting back tears, he told reporters: "During my training block (in Miami last month) I spoke to my team and told them I can't keep doing this.
"I needed to have an end point because I was sort of playing with no idea when the pain was going to stop.
"I said to my team, look I think I can get through this until Wimbledon.
"That's where I'd like to stop playing, but I'm also not certain I'm able to do that."
The three-time Grand Slam champion and former world number one has struggled for almost two years to recover from the injury.
He had surgery in Melbourne a year ago but said that his efforts to return to the top of the game had not been enough.
"I have an option to have another operation, which is a little bit more severe than what I've had before in having my hip resurfaced, which will allow me to have a better quality of life and be out of pain.
"That's something I'm seriously considering right now.
"Some athletes have had that and gone back to competing but there's obviously no guarantees with that and the reason for having an operation like that is not to return to professional sport, it's just for a better quality of life."
In 2016 Murray became the first British singles player to be officially ranked world number one, a position he held for 41 weeks. That year he won nine singles titles, including five in a row.
He has won three Grand Slam titles and reached 11 Grand Slam finals, also winning 45 singles titles in his career.