Oliver Lines stunned world number three Judd Trump to join his father Peter in the third round of the UK Championship.
The 21-year-old from Leeds, ranked 61st, followed up his father’s shock win over Neil Robertson with a deserved 6-2 victory at the York Barbican.
Lines led 3-0 and, after Trump rallied to 3-2 with two breaks of 50 plus, came through with some nerveless potting and shrewd tactical play.
Five-time champion Ronnie O’Sullivan earlier beat Scotland’s Rhys Clark 6-0.
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Lines said: “I had a bit of the ball-run early on and managed to take the chances that came. I am buzzing.
“It’s a relief. To beat a player as good as Judd on the biggest stage I have played on, on the TV as well – I am lost for words.
“I have never really performed on the TV before. To put that right and show people that I can play on the TV is very pleasing.”
Oliver Lines goes on to face Jimmy Robertson on Tuesday, after Peter Lines, 46, plays Liam Highfield on Monday.
O’Sullivan has yet to lose a frame in two matches after scoring a century in the second frame, making three breaks of 50 plus and rounding off with a stylish 131.
“So far so good. I played OK,” said the 40-year-old world number eight.
The Englishman, who faces Londoner Michael Georgiou in the third round on Monday, said that despite his magnificent form he was “blagging” it on the baize.
“I don’t want to spend the rest of my life hitting balls in a snooker room,” he added.
China’s Ding Junhui won five frames in a row to see off Scotland’s Ross Muir 6-2, the world number five saying afterwards he “switched off” and “lost concentration” in the early stages.
Liang Wenbo of China, last year’s runner-up, was beaten 6-4 by compatriot Yan Bingtao, and 2008 champion Shaun Murphy of England saw off Finland’s Robin Hull 6-3.
Meanwhile, Northern Ireland’s Mark Allen scored the first professional 147 of his career as he beat Rod Lawler 6-4 to move into the last 32.
The world number 10 said: “It’s great to get a maximum and get that monkey off my back. The pressure was on me big time because it was all there for me.”
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