Giant-killer James Cahill set his sights on winning the Betfred World Championship after his stunning first-round win over world number one Ronnie O'Sullivan.

The Blackpool amateur held his nerve to win 10-8 against a player he described as his "idol", who has won five titles this season, recently recorded his 1,000th career century and was chasing a sixth Crucible crown.

World number seven Judd Trump was at risk of a shock defeat of his own, trailing Thailand's Thepchaiya Un-Nooh 6-3 ahead of Wednesday morning's resumption, but all the talk was of O'Sullivan and his conqueror.

Cahill played on the professional tour from 2014 to 2017 and has already secured a return for next season, helped by another stunning upset of Mark Selby at the UK Championship at the end of 2018.

And after conquering O'Sullivan, the 23-year-old told BBC Two: "I'm here to win the tournament.

"I play every tournament to win otherwise I wouldn't play. You can't come to a tournament thinking you're going to get beat... or what's the point in playing?

"I've proved that I can play. I made the most centuries out of all the professionals in the qualifiers so the amateur thing doesn't mean anything.

"I don't have to prove anything now. I've got my two-year card, I've just beaten Ronnie – the world number one – and I'm going to give it my all in my next game and see what happens.

"You've got to believe you can beat anyone. I've got so much respect for Ronnie, he's such a great player and my idol really, but if you have too much respect for them I probably wouldn't have cleared up at the end there. I thought I was going to fall over at one point."

O'Sullivan has struggled with illness and insomnia ahead of the tournament and said: "My limbs are feeling very heavy. I have no energy.

"It's just life, it's not the end of the world. I tried to give it my best, I tried my hardest and it wasn't good enough."

Another tournament favourite is in trouble as Trump faces an uphill battle against Un-Nooh.

Trump trailed 3-1 at the mid-session interval and though he cut the deficit with a 141 clearance and again got within one frame at 4-3, his fellow left-hander pulled clear once more and needs just four more frames for victory.

There was more drama in the evening session as 2006 champion Graeme Dott recovered from 8-1 down to force a deciding frame against Stuart Bingham – only for the 2015 winner to prevail 10-9.

Bingham forfeited the 16th frame after failing three times to hit a red when not snookered, and Dott took it the distance but after both players had chances in frame 19, Bingham got over the line.

David Gilbert earlier beat Joe Perry 10-7, while Zhou Yuelong was on course for an upset of Mark Allen as he led 7-2 overnight.