John Higgins joined Ding Junhui on the Crucible casualty list as the four-time world champion was bundled out in Sheffield by his fellow Scot Alan McManus.
A second successive first-round loss at the Dafabet World Championship for Higgins came on the back of a misfiring performance, as he lost 10-7 to hand McManus, whose tartan trousers caught the eye, a shot at Ken Doherty in the last 16.
World number two Ding was edged out in a final-frame decider late on Monday night by little-known qualifier Michael Wasley, and now Higgins follows China's great hope out of the tournament, another big name gone.
McManus said he "just fell over the line", but it was a victory the 1994 Masters champion toiled for and carries him into the second round for the first time since 2005.
Higgins had taken the final two frames of their opening session on Monday to slow the charge of McManus, cutting his arrears to 6-3 overnight, but any momentum he might have felt failed to influence his performance on the resumption.
A fluked red gave Higgins the impetus to stop the early-morning rot and get back to 8-4, and after losing the next to go one frame away from defeat he belatedly found some vintage form, with the 38-year-old making 111, 67 and 94 in closing the gap to 9-7.
McManus, 43, trailed in the next frame too, but Higgins missed the blue when he looked like going just one frame behind and his good friend seized the unexpected match-winning chance.
McManus said on BBC Two: "It was a bit of a tense finish. It's never easy to put John away.
"Although he probably never played as well as he would have liked in most of the match, he came on strong towards the end and I kind of just fell over the line so I feel very fortunate.
"Now I play my fellow old-stager, Ken, and I'm really look forward to it. I'm sure Ken will be looking forward to it as much as I am."
Higgins had to concede his days as a regular title contender may be behind him.
He said: "It's been a bad season but I'm a lot happier compared to last year. I think I'm playing better - that's a crumb of comfort I can take.
"I feel as if there's something there that I can work on. There's been times when I've been sat here desolate, but I still think there's some decent snooker left in me.
"I'm not one of the top players that's challenging for events, I'm possibly a journeyman top 16 player now. The journeymen can have their day sometimes."
Meanwhile, Martin Gould fell 6-3 behind against Hong Kong's Marco Fu, who at one stage had a 147 maximum break chance but after 11 reds and blacks missed a treacherously difficult treble to stall on 88.