PARIS — Under pressure at the outset, Rafael Nadal already had cast aside three break points in his French Open semifinal's third game when, at 4-all, Juan Martin del Potro held another three.

If Nadal's march toward an 11th championship at Roland Garros was going to be stopped on this day, things were going to have to go del Potro's way right then. Both men knew that full well.

"That," del Potro would say later, "was my chance."

Ah, but there's a reason Nadal is 11-0 in semifinals at the French Open, a reason he is 10-0 in finals there — so far. He doesn't cede a thing and he doesn't let up. Nadal saved that second trio of break points Friday, held there, then broke in the next game to grab that set. It was part of a run in which he claimed 14 of the last 17 games to overwhelm the No. 5-seeded del Potro 6-4, 6-1, 6-2 and earn yet another spot in the title match at Court Philippe Chatrier.

In Sunday's final, Nadal will face No. 7 Dominic Thiem, a 24-year-old from Austria who is the only man to beat him on red clay over the past two seasons.

"He's a big favorite against everybody," said Thiem, who reached his first Grand Slam final by ending the out-of-nowhere run of 72nd-ranked Marco Cecchinato of Italy 7-5, 7-6 (10), 6-1. "Still, I know how to play against him. I have a plan."

Surely, so did del Potro. That crucial early juncture altered the course of things, though.

What went through Nadal's mind right then?

"Just thinking in a positive way and just thinking that I have to hold. 'I can't give him the game. If he wins the game, OK. But I will not give (it to) him,'" Nadal said. "That's the only way for me to approach the tough moments."

Truth is, there were not many the rest of the way, as Nadal finished with 35 winners and just 19 unforced errors.

This was the No. 5-seeded del Potro's first semifinal at Roland Garros since 2009. He missed the tournament every year from 2013-16 because of injuries, including three operations on his left wrist. In the fourth game Friday, del Potro clutched at his left hip after being wrong-footed by one shot from Nadal and was visited by a doctor at the next changeover, but said afterward it was not a big deal.

Soon enough, he was yelling at himself, a picture of exasperation thanks to Nadal's relentless ball-tracking and shotmaking.

"I couldn't play my best because of him," said del Potro, the 2009 U.S. Open champion. "His game is too good for me."

Too good for nearly everyone, nearly every time, on clay.

Nadal is now 110-2 in best-of-five-set matches on the surface, 85-2 in Paris. Over the past two years, including best-of-three matches, the Spaniard is 49-2 at clay tournaments.

Thiem is responsible for both of those losses — at Rome in May 2017, and at Madrid last month — which at least lends a little intrigue to Sunday's proceedings.

"If I want to beat him," Thiem said, "I have to play that way."

Thiem has been to the semifinals in Paris three years in a row, but he lost to eventual champions Novak Djokovic in 2016, then Nadal in 2017.

In Saturday's women's final, No. 1 Simona Halep of Romania will face No. 10 Sloane Stephens of the United States. Stephens won last year's U.S. Open; Halep is 0-3 in major finals.

Thiem went through one pivotal stretch against Cecchinato (cheh-key-NAH'-toe), a 25-year-old from Sicily who never had won a Grand Slam match until this tournament and was the lowest-ranked men's semifinalist at the clay-court major in 19 years. In 2016, Cecchinato was accused of match-fixing and suspended for 18 months, but he appealed, and his punishment was dropped on a technicality.

In the second-set tiebreaker Friday, Thiem went ahead 6-3, but missed out on three set points there, including a bad volley into the net at 6-4 that left him chewing ruefully on his left index finger.

"Not a very nice feeling," Thiem said.

A fourth set point for Thiem vanished because of one of Cecchinato's many drop shots.

Thiem weathered three set points for Cecchinato, at 7-6, 9-8 and 10-9. Then Thiem got to 10-all with a drop shot of his own.

At long last, Thiem converted his fifth set point when Cecchinato sent a forehand long.

"That was definitely the key," Cecchinato said. "After that, my level dropped."