Ronnie O'Sullivan has until the end of February to decide whether to end his break from snooker and defend his world title at the Crucible in April.
The four-time champion, 37, said in November he would miss the rest of the season because of "personal issues".
But he attended the Masters as a spectator and World Snooker chairman Barry Hearn said O'Sullivan could still enter the World Championship.
"He has until 28 February. He knows the date and it's up to him," said Hearn.
O'Sullivan, who has battled depression in recent years, sparked renewed speculation about his future with a surprise appearance at the Masters tournament at Alexandra Palace in London at the weekend.
He watched the semi-final on Saturday night between Graeme Dott and Mark Selby, with Selby winning the match 6-5 and going on to take the title for the third time.
"If I know Ronnie I think the reason he came Saturday night is because he's sitting at home watching it on telly saying 'I used to be good at that game'," said Hearn, who speaks to the player regularly.
"He's got a lot of issues he's trying to clear up. He knows the sport doesn't revolve around one person, but he knows we love him and we miss him.
"He's probably thought about coming back for the World Championship but you can't ever say what Ronnie is really thinking. He does tend to change his mind every 24 hours."
O'Sullivan was ranked nine at the end of last season, and although he has provisionally dropped to 20 after missing several tournaments, as defending champion he would qualify for the World Championship as top seed.
The Sun newspaper reported earlier this month that he has been working as a volunteer farm labourer in Essex.
"I've been cleaning out stables and pig sties, taking down fences, putting rubbish into barrels and clearing mud," he told the paper.
"It has been mainly manual work, also getting big bales of hay in to feed the animals. I was getting so bored I had to do something, and needed a goal to get out of bed in the morning.
"There are personal things I need to sort out before I can even think of a return. I have until February to make that decision about the Crucible, anyway, but I am still playing every couple of weeks at my mum's house."
Some leading players have said they would welcome a comeback.
Selby said: "He brings a lot to the game. Every time he plays, he always gets big crowds because he's entertaining to watch and he's a great player and one of the all-time greats.
"I think it will be a shame if he doesn't come back for the World Championship, especially because he's defending champion."
Beaten Masters finalist Neil Robertson added: "For me, if he comes back, he will be the favourite. He's such a talented player, he doesn't really need to keep practising. As long as he's practising once every couple of weeks, he'll be all right. We'd love to have him back."
Despite his absence, O'Sullivan is rated about 8-1 fifth favourite with most bookmakers for the world title, behind Judd Trump, Selby, Robertson and John Higgins.