British men's number one Cameron Norrie saw his hopes of qualifying for the ATP Finals take a blow after a straight-set loss to American Taylor Fritz in Paris.
Fritz won 6-3 7-6 (7-3) to progress to the last eight, where he will face world number one Novak Djokovic.
Significant points are on offer in Paris in the hunt for a spot in the year-end ATP Finals.
Norrie, 26, could have guaranteed qualification with a title win.
Both players played exceptional tennis as the match went to a tie-break in the second set.
Fritz continued his recent fine run of form to see off a battling Norrie, with the American producing a strong service game throughout, hitting 10 aces to the Briton's three.