Ken Doherty became the fifth member of the game's top eight to lose when he was beaten 5-4 by English left-hander Andy Hicks in the British Open in Brighton yesterday.
World number seven Doherty joined Mark Williams, Paul Hunter, Matthew Stevens and Peter Ebdon on the casualty list after losing his 4-2 lead.
Hicks highlighted his recovery with a break of 134 in the seventh frame and clinched the decider with a run of 103. The world number 51 is now through to his first major quarter-final since the 1996 European Open.
Hicks said: "I'm playing great snooker and proving to myself I can compete with the best players in the world. It's amazing how things can change."
Ronnie O'Sullivan's mood improved with his game as he stormed into the quarter-finals. O'Sullivan, who questioned his snooker future after scrapping past John Parrott in the previous round, fired two century breaks in defeating Stephen Lee 5-0.
The world champion, who extended his run of victories in ranking events to 13 matches, was far happier with life - with any thoughts of retirement apparently long forgotten.
"There's no point quoting me because what I say from one day to the next will be different," O'Sullivan admitted.
"It's important to play well and put in good performances for your whole well being. I didn't enjoy my match with John - but I enjoyed that (today)."
O'Sullivan, whose only British Open title success came 10 years ago, opened the match with a break of 127 and ended it with one of 100 to extend his record against Lee to nine victories in 11 meetings.