Mark Allen won a final-frame decider for the second time at the World Championship to set up a quarter-final with Mark Williams.
The Antrim player fought back from 7-3 down against Barry Hawkins to hold a 9-7 lead going into the evening session.
The former semi-finalist moved 12-9 ahead before Hawkins produced a comeback to level at 12-12.
Allen was on course for a maximum in the decider but it ended with a 96 break and a place in the last eight.
"I don't do things the easy way," said Allen after his dramatic victory.
"I was just hoping to get a chance in the last frame because he'd played so well.
"I've never been so happy to see someone hit a blue off the break and give me a chance, because in a deciding frame that's all you're wanting.
"Luckily I knocked the red in and made a good break."
Allen plays fellow left-hander Williams next and is relishing his clash with the world champion of 2000 and 2003.
"I'm looking forward to it," Allen added.
"I haven't played Mark in a long time. Obviously he's provisionally world number one now which is a major achievement considering he dropped to 42nd in the rankings at one point."
And when asked if this could be his year at the World Championship, Allen said:
"There's no reason why not - I've only got seven people left to beat. And obviously I'll only have to beat three of them on the way.
"Anyone who is in the quarter-finals can win. But Williams is going to be a tough man to beat."
The world number 11 edged out Matthew Stevens 10-9 at the Crucible in his first round game.