Reigning world snooker champion Ronnie O'Sullivan has pulled out of the rest of the 2012-13 season because of "personal issues" and may not return to the sport according to his manager.
The 36-year-old won his fourth world title in May but may not defend it.
Asked if he was looking to quit snooker permanently, his manager Django Fung said: "Yes. Let's hope not. You never know. Ronnie's an emotional player."
World Snooker chairman Barry Hearn was also unsure about O'Sullivan's future.
"Ronnie's had a lot of problems over the last nine months and perhaps even longer. He's not been a well boy and he's got a lot of personal issues he's got to resolve," Hearn told BBC Radio 5 live.
"He just felt it was time to take a complete break from snooker. I'm not sure whether it will be totally permanent, that's obviously going to be Ronnie's call, but he didn't want to mess anybody about.
"He doesn't enjoy entering tournaments and then for one reason or another not turning up. It's not good for the game either, the sponsors or television broadcasters. We need to know where we are and frankly I welcome this news."
After beating Ali Carter 18-11 to win his fourth world title in May, O'Sullivan spoke of his desire to take a six-month sabbatical from the sport and one month later he said he was taking time off from the game.
Fung confirmed that O'Sullivan was in a self-imposed exile "due to personal problems with his health" but stressed that his client was "mentally fine" and that "in six months time he may have decided to come back".
"We all have personal problems and some can handle them better than others," said Fung. "When he has these personal problems, Ronnie finds it difficult to concentrate on snooker.
"He's had glandular fever which has been dragging on for some time. He also has issues with his children and getting access and he's finding it difficult with all the travelling.
"He needs to get access to see the children and sometimes that coincides with tournaments."
After winning the world title, O'Sullivan accusing Hearn of "blackmailing" players and criticised plans for an extended 50-week, 27-event circuit.
Announcing his break from the game the following month, he said he would not sign the players' contract because it was "too onerous". As a result, he made himself ineligible for any World Snooker-sanctioned event.
He missed the first three ranking events of the season and slipped to number 17 in the world rankings - the first time he has been outside the top 16 since he entered the game's elite 19 years ago.
O'Sullivan returned to non-ranking action in September, losing in the first round of a Players Tour Championship event in Gloucester to world number 84 Simon Bedford.
He has since played six 'Snooker Legends' (external) exhibition matches against Jimmy White around the British Isles, concluding with O'Sullivan beating the six-time world finalist 5-4 in front of 1,300 fans in Liverpool on 25 October to level the series at 3-3.
The next day he withdrew - on doctors' advice - from the International Championship in China, which was won on Sunday by new world number one Judd Trump.
Despite being without the game's biggest star with the next major ranking tournament - the UK Championship - beginning in York on 1 December, Hearn praised O'Sullivan for a "mature decision" and said the sport remained healthy even without its biggest crowd-puller.
"I've known Ronnie since he was 12. We go back a long way and I know how serious he is in his mind," Hearn added.
"All I wish is the very best for the lad. He is a nice boy, has been a great, great player and whether we see him again, I don't know for sure. What I do know is this is definitely the right decision for him right now, and for snooker as well.
"Frankly the game's in a good spot at the moment. It's on a high right across Asia, right across Europe as well as in the UK. There's lots of other great players out there. The game doesn't revolve around just Ronnie O'Sullivan, but we'll miss him because he's an exciting talent."