Teenager Aaron Hill claimed a sensational second round victory over Ronnie O'Sullivan as he won 5-4 against the world champion at the European Masters.
The 18-year-old had let slip a 3-1 lead against the Rocket, who was in action for the first time since he triumphed at the Crucible last month.
While O'Sullivan levelled proceedings and moved ahead, Hill hit back to force a decider and a break of 78 sent him through to the third round where he will face Matthew Stevens.
Irishman Hill only turned professional earlier this year, but he showed nerves of steel to suggest the future could be bright for the Cork potter.
Hours before at the behind-closed doors event in Milton Keynes, Peter Devlin caused another upset against Mark Williams.
The 24-year-old had to hold his nerve to beat the three-time world champion in a decider at the Marshall Arena.
Devlin had been 4-1 up, but Williams responded only for the rookie to clinch a 5-4 victory with a break of 102.
"What a time to make a century, in a deciding frame against someone like that," the Londoner told World Snooker Tour.
"It's unbelievable. At 4-1, I knew I could have been pegged back. Players like that can win frames without you doing much wrong, so I was expecting a comeback.
"At 4-4, there was still a bit of adrenaline going but I managed to calm it down again."
Williams and O'Sullivan were not the only former world champions to exit in the second round with Ken Doherty knocked out by Mark Allen.
Northern Irishman Allen equalled history in the 5-0 win by hitting four consecutive centuries but fell short of the record with no hundred registered in the fifth frame.
Kyren Wilson, a runner-up at the World Championship, also progressed following a whitewash, while Ding Junhui had to dig in to beat Hossein Vafael 5-3.
Neil Robertson, who won the European Masters event in Austria at the start of 2020, made it through safely to the third round after a 5-2 win over Riley Parsons, but it was teenager Hill who was the talk of the town.
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