Ronnie O'Sullivan avoided an early Crucible exit as he roared back to beat Stephen Maguire in the first round of the Betfred World Championship.

After defending champion Mark Selby's defeat on Saturday night, there was the very real danger of O'Sullivan following him out of the tournament.

The 42-year-old five-time world champion trailed Maguire 6-3 overnight but won seven out of eight frames in the second session to pull off a 10-7 victory.

Maguire squandered chance after chance to assert his dominance of the contest on Sunday, and an O'Sullivan win began to look an inevitability long before he crossed the winning line.

As Maguire sat forlornly watching O'Sullivan mop up the final balls of the match, he would have reflected on where it all went wrong.

He led 49-0 in the 11th frame and had it at his mercy, but after looking fluent he under-cut a red and presented O'Sullivan an unexpected opening. He cleared the table with a break of 86.

O'Sullivan led for the first time at 8-7 when he pinched another frame that Maguire looked to be on the point of wrapping up, capitalising with a break of 53 when the Scot missed a long red.

Maguire's game had turned ragged. Early in the next frame he bungled a blue at high speed that rattled off a middle pocket knuckle and scattered the reds. O'Sullivan's response was a clinical 77 that put him one frame from victory. That was the 1,000th frame won by O'Sullivan at the World Championship.

In the final frame too, Maguire had an early chance but stalled before putting significant points on the scoreboard, and his race was run.

Ali Carter will tackle O'Sullivan in the second round after coming from 6-2 adrift to earn a 10-8 win against 2006 world champion Graeme Dott.

Essex cueman Carter lost to O'Sullivan in the 2008 and 2012 Crucible finals and has only beaten him once in his career.

The 38-year-old showed impressive form on Sunday in battling past three-time world finalist Dott, making breaks of 62, 108, 69, 56 and 63 across the session.

Dott said defeat was "hard to take" and added: "I was rubbish all the way through the game. He deserved it, he played a lot better than I did."

Dott said O'Sullivan would fancy taking on Carter, explaining: "I think Ronnie's got a good draw. He wouldn't lose any sleep playing me and I don't think he'll lose that much sleep over playing Ali."

Carter was surprised by Dott's self-assessment and said: "I think he was gutted that I beat him. I was gutted last year so it's his turn this year.

"He thought he'd done me today. Yesterday he thought the job was done, but it wasn't done. You can never, ever think you've got a match in the bag, so that'll be a lesson to him."

Looking ahead to the clash with O'Sullivan, which will start on Friday morning, Carter said: "I've been through a lot in my life, I've been very ill and got over it and I wouldn't have got over it if I didn't have that personality and fight in me. I used that today.

"It's great to be involved in a match with Ronnie. He's red-hot favourite, but I'm going to turn up, have a little go, and see what happens." 

Victory avenged Carter's defeat to Dott in the first round in Sheffield last year.

On the other table, Shaun Murphy led Jamie Jones 5-4 after their first session.

Murphy set an early marker for the £10,000 high-break prize with a 137 clearance in the third frame.

Northern Ireland's Mark Allen took control of his opening-round match against Liam Highfield, cmpiling breaks of 88, 56, 80, 52, 89 and 51 en-route to winning this morning's session 6-3.

They resume at 10am on Monday.

Rising star Kyren Wilson wrapped up a 10-3 win over two-time runner-up Matthew Stevens, and will face Murphy or Jones next.

Stevens said a sudden onset of illness on Friday night contributed to his defeat.

He said: "The first session was an absolute nightmare. I'd only slept for about an hour. I felt like death warmed up and I'm gutted, but that's life, worse things happen. I felt so ill yesterday and I'm just devastated.

"I was sweating, my stomach was in agony, it was horrible. But apart from that, fine. Take nothing away from Kyren though, he did a good job.

"I felt a million times better today and even at 7-2 I fancied my chances. It didn't happen, though, and that's the end of it.

"I'm not saying I'd have won if I was well, but it would have helped."

China's Lyu Haotian completed a debut win over Hong Kong's Marco Fu, winning 10-5 against a player who has missed several months of the season leading up to the World Championship after undergoing eye surgery.

Fu made two centuries in the match, but 20-year-old Haotian matched that and scored consistently heavily to set up a last-16 clash with Barry Hawkins or Stuart Carrington.