SHEFFIELD (Reuters) -Ronnie O'Sullivan began his quest for a record eighth world snooker title with a 10-4 defeat of fellow Englishman Ali Carter on Wednesday but admitted he arrived at the tournament with zero expectations after being out of action since January.

The 49-year-old snapped his cue at a tournament in Leicester in January and said he had been suffering 'stage fright'.

O'Sullivan, nicknamed The Rocket for his lightning-fast break-building, only decided to return to The Crucible for a 33rd successive year last week and initially looked a little rusty in the opening session of the match on Tuesday.

But after leading 5-4 overnight, he turned on the style by reeling off breaks of 109, 136, 132 and 131 to polish off Carter in quick time to set up a last-16 clash with China's Pang Junxu.

"I didn't have any expectations here, there were really no nerves going through the body coming here," O'Sullivan, widely-regarded as the best player ever to play the sport, said.

"I didn't expect to perform well based on the last three or four years. So I feel like I just wanted to make a little bit of a game of it, to be honest."

O'Sullivan, who pulled out of the Masters earlier this year to prioritise his mental wellbeing, has worked for a long time with renowned sport psychologist Steve Peters.

"I want to say a massive thank you to Steve," O'Sullivan, told the BBC. "My head's okay for life, but as far as getting on a snooker table has been really hard.

"He helped me before I went out yesterday, so I've got some mental tools to work with out there, just for this tournament, just to kind of just keep things tight. I'm always going to tinker, I can't get away from that, but it's just when to stop and when to just let your instinct take over."

O'Sullivan said he had previously lost his buzz for the game but reassured his huge fan club that he intends to carry on for at least another couple of years.

"If everything went great, I could probably get five, six years," he said. "If it doesn't, then I said I will still commit to two years and just focus on playing and just give myself every opportunity to try and finish on a nice feeling because the sport's been good to me and I love the game."

(Reporting by Martyn Herman, editing by Pritha Sarkar)