Jackson Page, 15, reached the second round of the Welsh Open in his first professional tournament but world number three John Higgins suffered a shock defeat.
Four time Wales Open champion Higgins was beaten 4-2 by Sam Baird.
Welshman Page came from behind to seal a 4-3 victory against Jason Weston and will now need more time off school.
“School let me have whatever time off I want because they know there could be a career in it,” he told BBC Radio Wales.
The teenager, from Ebbw Vale, had trailed 3-1 but recovered to eliminate world number 123 Weston.
In contrast, Higgins was unable to battle back after losing the first three frames of his match against Baird.
Elsewhere, 24 hours after his defeat by Barry Hawkins in the World Grand Prix final, Ryan Day beat David Gilbert 4-3, while world number 95 and six-time World Championship finalist Jimmy White was beaten 4-1 by 2016 finalist Neil Robertson.
Stuart Bingham, the 2015 world champion, beat Welshman Matthew Stevens 4-2, Wales’ Dominic Dale overcame Zhang Anda 4-0 and Shaun Murphy defeated Jamie Curtis-Barrett 4-0.
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