Ken Doherty reached the Embassy World Championship quarter-finals for a seventh time in eight years in Sheffield tonight - but only just.
The former world title holder from Dublin knocked out Glaswegian Graeme Dott 13-12 after nine hours and 13 minutes of play, including a 43-minute deciding frame, making it easily the longest match of the tournament so far.
Doherty, who defeated Shaun Murphy 10-9 on the last black in the first round, now plays John Higgins but must be back at the table at 10am tomorrow.
"I'm shattered," agreed the world number five. "But I'm just trying to give the punters value for money. How will I relax tonight? Maybe have a hot bath for an hour.
"There was so much pressure and tension out there," added Doherty, who faced potential elimination when he trailed 6-1 and 7-2.
"But I should have won 13-10. In the end Graeme was looking quite confident and I'm glad I fell over the line.
"That match is history now and hopefully I can play a lot better against John. I will certainly need to if I have any aspirations of winning the tournament."
Doherty resumed the day faced by a 9-7 deficit but took the first four frames of the final session to gain a commanding position at 11-9.
Dott pinched the 21st frame for 11-10 but Doherty knocked in a half-century to move 12-10 up.
Just when he thought he had done the hard work, Dott came back strongly. He levelled at 12-12 as Doherty scored only nine points.
It meant a fourth-successive deciding frame for Doherty at The Crucible after his previous win over Murphy and last season's close encounters against Mark King and Stephen Hendry.
"I think I proved a few people wrong the way I came back," said Dott. "When it went 7-7 people probably thought that was it and no doubt they thought the same thing at 9-7 and 11-9.
"But I think it deserved to be 13-12. I thought I was the stronger player in the last frame but every time I potted a long red I didn't land on anything."