British number one Cameron Norrie was beaten in straight sets by Russia's Aslan Karatsev in the Zhuhai Championships quarter-finals.
Karatsev, 30, who knocked out Andy Murray in the last 16, edged another hard-fought contest on Sunday.
He will face either Germany's Jan-Lennard Struff or Japan's Yoshihito Nishioka in the semi-finals.
After losing the first set, Norrie backed up a break of serve to go 3-1 up in the second and then served for the set at 5-4.
But Karatsev broke back before again edging out Norrie in a tie-break.
Russian top seed Karen Khachanov takes on American Sebastian Korda in the second semi-final.