UK champion Zhao Xintong is out of the World Grand Prix after a 4-2 defeat to Martin Gould on Monday night.
The top seed rolled in a 101 break to lead 2-1 early, but Gould rattled off breaks of 75, 52 and 79 to spring a minor surprise.
Zhao has lost in the first round of both ranking tournaments since capturing the first Triple Crown event of the season, only tasting victory in a pair of low-key qualifying matches for next year's German Masters.
Reigning Masters champion Yan Bingtao had no such problems as he beat Mark King 4-1 to earn a second-round meeting with Gould.
Yan stamped his authority on the match with a 111 break to move into a 3-1 lead before completing a straightforward victory.
Kyren Wilson suffered a surprise defeat to in-form Anthony Hamilton, who held his nerve to win a decider having surrendered a 2-0 lead.
Hamilton made the last 16 of the UK Championship before some solid results in qualifying events over the last fortnight, and after preventing Wilson from scoring a single point across the first two frames, he went on to progress to round two.
Finally, last year’s finalist Jack Lisowski won a battle of the left-handers as he beat third seed Mark Williams 4-3.
Lisowski, seeded 30, will be hopeful of a similarly deep run having landed in the weakest quarter of the draw, and could go on to face either Ronnie O’Sullivan or Scottish Open winner Luca Brecel in the semi-finals.