Defending champion Mark Selby crashed out of the Betway UK Championship following a 6-3 second-round defeat to Scott Donaldson.
The result is even more remarkable considering Donaldson had won just one match this season before the match, a 6-2 victory over John Astley in the first round in York, but the Scot held his nerve to claim the biggest victory of his career.
Selby took the opening frame courtesy of a 68 break and extended his advantage before the 23-year-old halved the deficit with a wonderful run of 88.
Donaldson won the next two to nudge ahead for the first time in the match before Selby levelled following another half-century run.
The Scot maintained his composure and rattle off the last three frames to earn the shock win after compiling breaks of 90 and 77 to advance to the third round of the competition for just the second time in his career.
Mark Allen is through to the next round after a 6-4 win over Oliver Lines.
But Ken Doherty is out - he lost 6-2 to fellow former world champion Neil Robertson.