Ronnie O'Sullivan assured snooker fans "I haven't gone yet" after winning his fourth World Championship title at the Crucible tonight.

The "Rocket" had threatened to follow Stephen Hendry into retirement ahead of the final against Ali Carter, which saw him complete an 18-11 win.

Carter joked immediately after his second final defeat "Maybe if he retires I might win it" - but O'Sullivan immediately dismissed such thoughts.

"A few people doubted me but I'll let them know when I'm not ready," he told BBC2. "I certainly haven't gone yet."

O'Sullivan tonight put the seal on his glorious tournament - and perhaps one of snooker's great careers too - by carrying off the title for a fourth time.

Snooker's most exhilarating performer feared he would never add to the Crucible crowns he landed in 2001, 2004 and 2008 but now looks like he may add more.

Twelve months ago he had decided to pull out of the World Championship until a late change of heart saw him line up.

Now, after putting heart and soul into a push for glory in Sheffield, and with sports psychiatrist Dr Steve Peters helping him find peace of mind, O'Sullivan is on top of the world again at the age of 36.

The Chigwell cueman becomes the oldest champion since Ray Reardon, who at 45 landed his sixth title in 1978, and if it were any other player such a success might be considered one which could spur a late career flourish.

O'Sullivan had the Crucible crowds on tenterhooks though, as he entered the final on the back of a retirement warning.

It could come tonight, he had said, although considering he first threatened to quit at the age of 18 and has repeatedly done so throughout his career it was hard to know what he would decide.

Tonight's concluding session saw Stephen Hendry, the man who retired on the tournament's middle Sunday, take the final bow of his 17 days in Sheffield before the finalists made their entrances.

There was a warm welcome for Carter, whose surprising venture to the final has taken in a stunning comeback over last year's shock merchant Judd Trump, a helping hand from Peter Ebdon, and gallons of carrot juice.

Carter believes the juice has helped him to stave off the effects of Crohn's disease which at the turn of the year had become so destabilising that he too considered quitting snooker.

Ebdon has had an impact on his game too, no doubt with tactical advice that helped him past Trump and Stephen Maguire, but in the final he was found lacking the attacking threat to trouble O'Sullivan.

When O'Sullivan made his entrance it was to a raucous reception, and the crowd's long-time favourite delivered the triumph so many of them craved.

"I'm not going to worry about 900 people shouting for Ronnie," Carter said, heading into the match.

"I might have three or four shouting for me, but I'm in the final and I've got a chance."

The 32-year-old from Tiptree was only very briefly even on level terms though, O'Sullivan pulling away from 3-3 to take a lead he would never look like relinquishing.

O'Sullivan made three centuries in the match, including the 141 he registered yesterday that enters the record books as the highest break in a World Championship final, and the dash to 101 in the opening session today which was sparked by a silky smooth long red.

Tonight, 15-10 ahead entering the final session, he began in the manner of a champion with a 70 break that meant Carter required eight of nine frames to achieve his title goal.

And it was soon all over, O'Sullivan polishing off his triumph with a sharp 61 break.

O'Sullivan did, however, reflect on how tough the tournament had been and revealed he will take an extended break to spend time with his young family.

Accompanied by his son Ronnie Jr ahead of the trophy presentation, he said: "I'm having a good six months off now to spend time with this little man, and my little daughter.

"When I saw him this morning, the pressure lifted. I could hear him saying 'come on Dad', that was the time to get emotional.

"I'll have a nice, good break and assess the situation, but it's all good. I'll just enjoy the moment.

"It was very, very hard. For anyone to come here and stand 17 days - it's an endurance test.

"It's not as much about the snooker, it's just controlling the emotions.

"I came here to entertain in this tournament, I wanted to show people what I was capable of."

He admitted the influence of sports psychiatrist Dr Peters on his return to form this season, after a slip down the world rankings and several previous threats to retire.

"I wouldn't have been playing if it wasn't for Steve," he said.

"I said to him when I met him, 'I don't want you to be able to help me', and he said that's the normal reaction.

"It's been tough, I've had to face things I didn't want to face and don't wanna keep facing, sometimes I just want to run."