Novak Djokovic came up short in his latest bid for a record 25th grand slam title as Jannik Sinner reached his first French Open final.
Djokovic, who turned 38 last month, was bidding to become the oldest winner of a major title.
But in Sinner - 15 years his junior - the Serbian was essentially playing a younger, fitter version of himself.
It was a high-calibre contest befitting a semi-final between the current world's best player and arguably the greatest of all time.
But it was Sinner who won the big moments and came out on top with a 6-4 7-5 7-6 (3) victory.
Sinner, who holds the US and Australian Open titles, is now on a 20-match winning streak at grand slams.
He will play defending champion Carlos Alcaraz, the second seed, in a blockbuster showdown on Sunday.
They may have won the last five grand slams between them, but it will be the first time they have met at one in a final.
Just to make Djokovic feel even older, it will be the first major final to be contested between two players born this century.
With Aryna Sabalenka and Coco Gauff the last two women standing, Roland Garros will be the first grand slam to feature the top-two seeds from both the ATP and WTA draws in the finals since the 2013 US Open.
Djokovic has won three titles on the Paris clay but the surface was not his friend when Sinner broke in the first set after the ball kicked up violently off the dust and left him swinging at thin air.
Early in the second set Djokovic won a spectacular 26-shot rally, the pair exchanging drop shots before the Serb stretched to volley into an open court before milking the applause from the crowd.
Djokovic forced a first break point as Sinner served for the set and when the Italian netted a forehand, he was finally breached.
But the 23-year-old hit straight back and, after Djokovic received medical treatment on his left thigh at the changeover, he wrapped up the second set.
Djokovic kept fighting and had three set points to take it into a fourth in a 10th game, but Sinner wriggled out of that hole and secured victory in the tie-break after three hours and 16 minutes.
Once again Djokovic proved he still belongs in the latter stages of the grand slams, but the wait for the milestone 25th title goes on.
He will face Alcaraz for the title on Sunday after Lorenzo Musetti retired in Friday's first semi-final.
Italian Musetti won the first set and was playing some exquisite tennis under the roof on Court Philippe-Chatrier.
But the 23-year-old had treatment on his leg during a one-sided third set and called it a day after Alcaraz won nine games in a row with the score 4-6 7-6 (3) 6-0 2-0.
There were echoes of a match here four years ago when Musetti retired against Novak Djokovic at 4-0 down in the fifth, later saying he was not injured but that he quit because he was "not able to win a point".
Alcaraz, who will bid for a fifth grand slam title on Sunday, said: "It is never great getting through like this.
"Lorenzo is a great player. He has had an incredible clay season. He's one of the few players who has achieved the semi-finals. I wish him all the best and a quick recovery.
"The first two sets were really tough. I had chances to break his serve in the match and I couldn't make the most of it.
"He was playing great tennis. When I won the second set, there was relief. In the third I knew what I had to do - pushing him to the limit and trying to be aggressive.
"I was more calm and I could see this more clearly and I could play great tennis."
An exciting match looked on the cards when at 5-4 Musetti, who had not previously threatened the Alcaraz serve, suddenly broke to take the first set.
Alcaraz served for the second set but the tension he was feeling was palpable as Musetti broke straight back.
However, Alcaraz reset in the tie-break and, although Musetti saved two set points, he dumped a third into the net.
Musetti planted his hand onto his face after a bad miss handed the initiative to Alcaraz, who grabbed the early break in the third.
Suddenly the shackles were off for Alcaraz while Musetti was labouring, winning just five points as the set disappeared over the horizon.
The eighth seed had received treatment on his left leg but was still clearly hindered and when Alcaraz broke for 2-0 in the fourth, he decided he had had enough.
