World number one Mark Selby is out of the World Open, losing 5-4 to Noppon Saengkham in China.
Thailand’s Saengkham opened up an early 3-0 lead, before Selby mounted a recovery with breaks of 102 and 50.
Saengkham, 26, then edged back ahead, before Selby, 35, forced the decider, which the world number 53 won 58-55 to reach the quarter-finals.
World champion Mark Williams scored four half-century break to reach the quarters with a 5-1 win over Joe Perry.
Williams will next play Jack Lisowski, who came back from 3-0 down to beat Kyren Wilson 5-4.
World number 26 Xiao Guodong is Saengkham’s next opponent after beating Anthony Hamilton 5-3.
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