World number 113 Hammad Miah shocked former world champion Judd Trump on the final black to reach the third round of the British Open in Cheltenham.
Trump led 2-1 and 3-2 in a thrilling match that saw both players hit two centuries, but was taken to a deciding frame and a black ball decider.
Miah then took advantage of a poor safety shot by the world number four to pot the black and seal one of the biggest wins of his career.
“It feels amazing,” said Miah, 30.
Speaking to World Snooker Tour, Miah added: “I haven’t had a good start like that in a match for a very long time.
“It felt good to keep up with Judd and it gives you the extra belief that you can really do it if you just focus.”
With world number one Ronnie O’Sullivan absent and world champion Luca Brecel already eliminated, the tournament at the Centaur feels wide open.
Another upset saw 2010 world champion Neil Robertson well beaten 4-1 by last season’s World Championship semi-finalist Si Jiahu of China.
Australian Robertson took the first frame with a break of 59, but 21-year-old Si reeled off four straight frames, including a break of 107, to comfortably progress.
Elsewhere, three-time world champion Mark Williams overcame Stephen Maguire 4-2, while there were also victories for Fergal O’Brien, David Gilbert, Hossein Vafaei, Ali Carter, Jack Lisowski and former Crucible winner Graeme Dott.
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