Argentina's Juan Martin del Potro came through a clash of the titans against Marin Cilic to reach his first French Open semi-final for nine years, winning a rain-delayed duel 7-6 (7-5) 5-7 6-3 7-5.
The 29-year-old set up a clash with 10-time champion Rafael Nadal.
Play resumed with the towering fifth and third seeds locked at 5-5 in the first set tiebreak and del Potro needed only two points to pocket the first set on Thursday.
The second set was also dominated by serve until Cilic fired himself up to break at 4-4 - a furious del Potro throwing his racket at the changeover.
Croatian Cilic played an awful game when serving for the set but he was gifted another chance to serve for the set after breaking del Potro again and at the second time of asking he levelled the match.
Del Potro dipped at the start of the third and Cilic had points for a double break but the burly Argentine, roared on by chants of "Delpo Delpo" recovered his drive to hit back from 0-2 and take the set.
Cilic, bidding to reach the semi-finals for the first time after falling in the last eight 12 months ago, kept his nose in front in the fourth.
He buckled at 5-5 and sent a backhand long on break point, leaving del Potro to serve for the match, which he did with ease as Cilic sent three more backhands out.
"It's tough to speak now," del Potro said.
"It has been a long time without a good feeling in my body. I have had three surgeries on my left wrist and I was close to quitting. I don't have any words."
Nadal, meanwhile, lost his first set at the French Open since 2015 but that blip did not stop him marching into the semi-finals with a 4-6 6-3 6-2 6-2 victory over Diego Schwartzman.
The world No.1 had looked out of sorts on Wednesday, with the Argentine leading by a set and a break when the players were first called off the court.
Upon resumption, the Spaniard gradually improved before rain brought an early end to the day with Nadal on the brink of winning the second set.
It was a different story on Thursday as Nadal won 12 of the first 13 points before cruising into the last four.
"Of course the stop yesterday helped because it was in a tough moment of my match," said Nadal.
"He was playing great, and I was playing too defensive. I felt that I was playing a little bit under more stress than usual, and he was able to take control of the point too many times.
"I played more aggressive. I continued the level of intensity that I played after the first stop. And, in my opinion, the match changed."