Ronnie O'Sullivan avoided an early exit as he completed his stunning fightback to beat Stephen Maguire 10-7.
He won seven out of eight frames on Sunday as Maguire's challenge faded.
Maguire squandered chance after chance to reassert his dominance, and an O'Sullivan victory began to look an inevitability long before he crossed the winning line.
O'Sullivan said: "I suppose every match is there for the taking and you just have to let it unravel. I was lucky to get through, and that's good for me and unlucky for Stephen.
"It's the toss of a coin with a lot of these matches. I'm lucky in the sense it's nice to still be in the tournament."
He admitted his performance in the first session had let down the paying spectators, saying: "It was so embarrassing and I felt like I wanted to give them all their money back. I was gutted. They took a Saturday afternoon out to come and watch a bit of snooker. Thank God Stephen potted a few balls. I was missing balls all over the gaff."
He spoke at length about his dedication to a healthy diet and the belief it will help him live a long life.
"I think I'm going to live until about 200 now, I feel so good," he said.
"The way I'm feeling now is frightening. I feel better now than I ever have.
"I never thought I'd like celery but I'm eating so much of it now I'm going to look like a celery stick at the end of this tournament."
Maguire said: "He'll probably be thinking that he got out of jail there so he'll probably be more dangerous than he usually is (for the rest of the tournament).
"Yesterday I could have won the match. Once I went 6-3 I was obviously happy but I think he'd have been delighted with 6-3, the way he was playing."
Maguire felt the match began to get away from him when he wasted a big chance to win the 13th frame and go 8-5 ahead. He sensed O'Sullivan was a different player from that moment.
"I could see he just stepped it up a little bit," Maguire said.
"He never gives up playing me. I've seen him play matches where he throws in the towel and I wish he did that against me.
"That match was there for the taking but he's finished me off in the end quite convincingly."
Captain Carter edges epic
Ali Carter became the first man younger than 40 to reach round two with a 10-8 victory over former Crucible champion Graeme Dott.
With the match locked together at 8-8 deep into Sunday afternoon, officials confirmed it would be played to a finish with the evening session delayed if that became necessary.
Carter, though, made sure it would not be, taking a messy 17th frame before a fine 63 break sealed a clash with O'Sullivan in the next round.
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."
Elsewhere, Shaun Murphy edged the first session of his clash with Jamie Jones 5-4, while Mark Allen leads Liam Highfield 6-3 having taken each of the final three frames in the morning.
Murphy set an early marker for the £10,000 high-break prize with a 137 clearance in the third frame.
Wilson sees off ill Stevens
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."
Wilson said his win was "very satisfying", adding: "Matthew's a very classy opponent. He's been there and done it before here, and a 10-3 scoreline is very flattering."
The 26-year-old from Kettering said he had been under the weather too with a "bit of man flu" and praised "classy guy" Stevens for twice calling fouls on himself.
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.
Fu had no complaints about his defeat, calling the outcome "very fair".
"Overall he was by far the stronger player," Fu said.
He said Lyu's prospects of further success in the tournament were "a matter of whether he can maintain his consistency".
Fu said his eyes were fine and he would return to the tour on a full-time basis next season, but he added: "Coming to the Worlds was probably a bit too soon for me."
Sheffield-based Lyu said: "I'm obviously happy to win. I was happy to be able to perform well in this match.
"I expected to be nervous but it turned out to be very enjoyable."