Greek fifth seed Stefanos Tsitsipas reached his first French Open semi-final with a commanding straight-set victory over Andrey Rublev.
Tsitsipas, 22, took advantage to turn the tide and earn a 7-5 6-2 6-3 win.
He will play top seed Novak Djokovic or 17th seed Pablo Carreno Busta for a place in Sunday's final in Paris.
Meanwhile Petra Kvitova reached the French Open semi-finals for the first time since 2012 as an emotional run continued with victory over Germany's Laura Siegemund.
Two-time Wimbledon champion Kvitova, 30, is bidding for a first Grand Slam title since returning from a career-threatening knife attack in 2016.
She will face American Sofia Kenin for a spot in Saturday's final.
Australian Open champion Kenin progressed 6-4 4-6 6-0 against compatriot Danielle Collins, after the world number 57 needed treatment in the deciding set.