Mark Selby fell victim to the Crucible curse and a rookie Scot with pots of class as Anthony McGill pulled off a monumental Betfred World Championship shock.

Qualifier McGill exuded calm assurance as he saw off the defending champion 13-9 to book a quarter-final place, never appearing overawed by the match or the gradual position of control he developed over the course of Friday.

The 24-year-old from Glasgow, making his debut at the tournament, finished off Selby with a break of 82.

As they shook hands, the man who beat Ronnie O'Sullivan in last year's final told McGill he could go on to capture the title.

McGill said: "I'm just ecstatic. To beat the world champion at the Crucible, I just can't believe it.

"No-one expected me to win. I wasn't expecting myself to win, I was just hoping to put up a decent fight and try my best.

"To beat Mark 13-9 is just a dream."

McGill was the architect of Selby's demise, but the famous curse, which has at the very least become a factor lodged in the back of every first-time champion's mind, will be cited too.

No maiden winner of the World Championship in Sheffield has returned a year later to retain the trophy, with Selby becoming the 16th man to falter, joining a list that includes greats of the game such as Steve Davis, Stephen Hendry and O'Sullivan.

Deposed champion Selby said: "He played fantastically all match and thoroughly deserved to win.

"Every time he got a chance he seemed to punish me.

"I said to him at the end that if he played like that there's no reason he can't win it."

And with the curse in mind, Selby said: "I've no embarrassment in losing. You look at the greats who've won it for the first time and not defended it."

McGill will be careful not to let his mind drift beyond a last-eight clash with Shaun Murphy or Joe Perry, who begin their second-round clash on Sunday.

And as for thoughts of landing the trophy, McGill said: "I've knocked out the world champion, so you think whoever knocks him out could - but I don't know.

"I don't think people will be fearing me. I'm probably a good draw in the quarter-finals of the World Championship to be honest."

But after seeing off Stephen Maguire and Mark Selby, McGill will be eyeing more victims.

"It seems like every time I win a game it's the biggest win of my career," he said. "Fingers crossed it keeps happening."

McGill has been quietly earmarked for greatness by those who know him best. Former Crucible semi-finalist Alan McManus, a close friend and mentor, has tipped the former Junior Pot Black runner-up to take the trophy in Sheffield one day, and O'Sullivan said there would be no worthier champion because of his dedication.

Hendry gave him a thumbs-up as they briefly crossed paths on Friday, the approval of the seven-time champion bringing a smile to McGill's face.

In 2005, Murphy came through qualifying and went on to lift the title. A similar thing could happen here this year.

McGill is a slender, shy man with a short ginger crop and a giggle he often breaks into around the table. Selby, the Jester from Leicester, found little to laugh about.

When McGill fired in an 87 break to lead 12-7, Selby's tournament was almost over. The champion edged the next to earn an interval, and returned with a break of 101, but McGill slotted a terrific red to launch his victory charge.

Tam, his father, drives lorries through the night, on a familiar Glasgow-to-Coventry route, and McGill feared he would struggle to negotiate time off for a Crucible trip, but he and mother Helen, a nurse in Glasgow, were in the arena to witness their son's finest moment yet in a five-year professional career.

"I'll go and find them now and give them a big hug," McGill said.

McGill could find himself the last Scot standing come Saturday evening, with former champions Graeme Dott and John Higgins in danger of elimination.

Dott fell 11-5 adrift of Stuart Bingham, while Higgins slipped from 7-5 in front to 9-7 behind Ding Junhui, China's perennial Crucible underachiever.

Northern Ireland's Mark Allen built an early 5-3 lead over Barry Hawkins, the 2013 runner-up, in a match that ends on Saturday evening, when O'Sullivan, perhaps glad Selby has gone, begins his second-round match against Matthew Stevens.