Defending champion Shaun Murphy forfeited a frame as he was beaten 6-4 by Mark Allen in round one of the Masters at London's Alexandra Palace.
Allen was leading 3-2 when Murphy failed to hit the reds with three successive shots when not snookered.
"I had to man up, take a deep breath and play the right shot," said the 2005 world champion, "Unfortunately I got it completely wrong.
"Did I lose the match because of it? No, I don't think so."
Allen said: "I'm very happy with the way I played, I scored heavily, took my chances well and got over the line in the end."
He will face either Barry Hawkins or Joe Perry in the quarter-finals.
Stuart Bingham won his first ever match at the Masters, beating Ding Junhui 6-4 in a tense encounter that lasted close to four hours..
The world champion also missed out on a maximum 147, potting 15 reds and 15 blacks in frame three but missing the yellow having made 120.
He will now face either John Higgins or Liang Wenbo.