Judd Trump and Ding Junhui were among the second-round casualties at the World Open in Yushan, China.
World number five Trump lost 5-3 to fellow Englishman Gary Wilson, the world number 41.
China’s Ding, the world number six and the defending champion, lost a final-frame decider against Robert Milkins, ranked 33rd.
World champion Mark Williams and world number one Mark Selby advanced safely to the last 16.
Ding rallied from 2-0 down to lead 3-2, and after going 4-3 down, won frame eight with a break of 55, his highest of the match.
Both players had chances in the final frame but Ding’s missed blue to a baulk corner proved to his last shot of the contest.
Breaks of 62, 113 and 112 helped former China Open finalist Wilson to a 3-1 lead over Trump and though the left-hander levelled at 3-3, Wilson advanced after runs of 40 and 50.
Former world champion Neil Robertson, who won the first tour event of the new snooker season at the Riga Masters last month, lost 5-3 to Ricky Walden.
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