Australia's John Millman has lost his Open Sud de France quarter-final with big-serving Frenchman Paul-Henri Mathieu 7-6 (7-5) 5-7 6-3.
Henri Mathieu sent down 17 aces to seal the win and now faces Alexander Zverev for a place in Sunday's final.
Defending champion Richard Gasquet of France defeated Marcos Baghdatis of Cyprus 6-4 6-4 to reach the semi-finals.
"It's always delicate to play against a very good player who you've never beaten before, but I played a solid match," Gasquet said.
A three-time grand slam semi-finalist, Gasquet is chasing his 13th career title and he next plays Germany's Dustin Brown, who won his quarter-final against Ruben Bemelmans 6-3 6-3.
Teenager Zverev beat Michael Berrer 6-7 (2) 6-2 7-5 in an all-German match to reach the last four.
The 18-year-old saved 16 of 18 break-points faced, including 10 in the third set, and won on his fifth match point.
"It wasn't easy to use all the chances because of (his) great play," said Zverev, who beat 2014 US Open champion Marin Cilic in the second round.
"You can have an unbelievable day like I did against Marin. You don't have those days all the time, but I got the win."
