Snooker: Ronnie O'Sullivan and Judd Trump level after first session in their World Championship semi-final

O'Sullivan took a 4-1 lead before being pegged back

Time will tell whether Ronnie O'Sullivan carries out his latest threat to quit snooker but if he is to walk away then sessions such as today's opener to his Betfair World Championship semi-final against Judd Trump are to be savoured.

The four-time champion led 4-1 in an absorbing contest, before Trump, the natural heir to O'Sullivan as the sport's great crowd-pleaser, rattled off three frames in a row to draw level.

So they will resume tomorrow, for morning and evening sessions, at four frames each in the race to 17, their target for a place in the final.

O'Sullivan fired in breaks of 65, 75 and 89 on his way to the three-frame cushion, and looked then a strong favourite to secure an overnight lead.

But 23-year-old Trump, who said prior to the match that he would not be scared of O'Sullivan, proved good to his word as he gutsily fought back.

He seemed down and out in frame seven when O'Sullivan built a handsome lead after a break of 56, which was most noteworthy for the sublime shot that kept it going on 36.

Faced with a difficult positional shot on the pink, with the reds awkward, he screwed the cue ball off the colour and swung it around three cushions and into a cluster of four reds on the top cushion. It elicited a handy split, but O'Sullivan could not convert the break into a frame-winning clearance.

Trump got back to the table with an outstanding long penultimate red, laid a smart snooker behind the green and forced a seven-point foul. Trump drilled a red to the middle pocket and made it count by clearing to the pink for 26 to snatch the frame.

Buoyed by that, Trump fired in 72 in the final frame of the session to end on a high.

O'Sullivan last night claimed this would be his final World Championship.

"This is my last farewell, it's my swan song. I'm happy; I'm done," said the 37-year-old.

"I didn't know what was going to happen here but I've made a little bit of money now so I can go and pay the school fees now for the next two years.

"But really I don't think snooker is for me."

O'Sullivan has repeatedly floated the prospect of retirement during his career, and bookmakers already make him odds on to play at the Crucible next year.

The scepticism is understandable, and six-time world champion Steve Davis believes O'Sullivan's remarks could be considered "disrespectful".

Davis, speaking to the BBC, said today: "We know full well that Ronnie O'Sullivan's interviews are a bit like the British weather: they're changeable.

"But there's a dilemma for the snooker fan. They love what comes off the end of his cue; they sometimes hate what comes out of his mouth because it is sometimes disrespectful to snooker.

"The question to ask for every snooker fan is: 'Is it better for Judd Trump to win this match rather than Ronnie O'Sullivan even though Ronnie is such a breath of fresh air when he plays great?'

"It's a tough question to ask. If he's saying he's not going to play on the table and that's true, what use is he to the future of snooker?

"We'd love Ronnie O'Sullivan to be playing more snooker, not less."

Dennis Taylor, world champion in 1985, believes that rather than walk away entirely, O'Sullivan should consider entering just the World Championship every year.

And he believes he could better Stephen Hendry's record of seven world titles by doing so.

Taylor also suspects O'Sullivan may have been using kidology ahead of the crunch clash with Trump. What he achieved with his revelations last night was to take all the attention away from showman Trump.

Taylor told Press Association Sport: "Ronnie's said this all before and you have to take it with a pinch of salt sometimes. He loves playing the game still as you can tell by the way he started against Judd.

"There'd be nothing wrong with him winning the World Championship every year and playing in nothing else.

"And then when he's overtaken Stephen Hendry I'll say he's the greatest player that's ever picked a cue up, so maybe that's what he's going to do.

"You never know with Ronnie, maybe it's a little bit of psychology. You never know what's going on in the brain of a genius."

Taylor suspects that O'Sullivan's departure from the tour would be considered no great loss by his fellow players.

"He'd be sorely missed by some but not by the players. We had 10 different winners this season with Ronnie not playing so they won't mind if Ronnie doesn't want to play," Taylor said.

"It means more money, more titles for them. I'd be surprised if he does finish but you never ever know with the Rocket."