The 25-year-old McGill fought back from 6-4 down to win six of the last eight frames, making a century and five more breaks over 50.

The player nicknamed the Smiling Assassin captured the imagination with a run to the quarterfinals last year on his Crucible debut, knocking out Stephen Maguire and Mark Selby before losing to Murphy.

With Murphy following Stuart Bingham on the road out of Sheffield, the result means that both of last year's finalists have fallen at the first hurdle.

"I suppose I could win it," said McGill. "I've got a cue in my hand and I'm still in it. I didn't come here to win, I'm here just to try my best and see where that gets me."

Maguire lost in the first round at the Crucible for the fourth year in a row as Alan McManus scored a 10-7 victory.

Veteran McManus, aged 45, is making his 20th appearance at the Crucible and is through to the last 16 for the 15th time.