Sinner faces Djokovic as reigning champion Alcaraz eyes French Open final
Sinner has stormed into the last four without dropping a set while Djokovic impressed in a four-set win over last year's runner-up Alexander Zverev in the quarter-finals.
Alcaraz delivered his most convincing display of the tournament in a ruthless demolition of Tommy Paul in the last round, while the in-form Musetti is targeting his first major final.
Top seed and three-time Grand Slam winner Sinner takes on the most successful man ever to play the sport in a rivalry that connects one generation to the next.
Sinner, 23, and Djokovic, 38, have split their eight meetings, but the Italian has won four of the last five matches to signal the undeniable power shift in men's tennis.
Sinner is riding a 19-match winning run at Grand Slams as he chases a third successive major title, looking to go a step further at Roland Garros than last year's semi-final loss to Alcaraz in five sets.
"(Djokovic) has shown now in the last period that he is back to the level," said Sinner.
"It's going to be... very, very difficult. He's such an experienced player, 24 Grand Slams. I think that says everything."
A week before Roland Garros, Djokovic had not won a single match on clay this year.
But after capturing his 100th ATP title in Geneva and arriving at the French Open battle-tested, the 38-year-old Serbian has steadily hit his stride.
The three-time Roland Garros champion is two wins away from a record-breaking 25th major to move him out in front of Margaret Court, but he is aware of the magnitude of the task ahead.
"Jannik is in tremendous form, and he has been the best player for the last couple of years," said Djokovic.
"There is no bigger occasion for me... I just hope that I will be able to physically keep up."
Djokovic could become the first man to beat the world's top three players en route to a Grand Slam title after defeating third-ranked Zverev in the last eight, with world number two Alcaraz a possible final opponent.
"I think at the moment he's a bit underrated, to be honest," Zverev said after his loss to the Serb.
"I think like a lot of people count him out already, but this year he's had wins over Carlos at the Australian Open, he has had a win over me at the French Open. Forget the age. I think for any player, those are pretty good results."
Alcaraz continues title defence
Alcaraz resumes his burgeoning rivalry with Musetti, hoping to back up victories over the Italian in the Monte Carlo Masters final and Italian Open semi-finals.
But Musetti, who also reached the last four in Madrid, is one of the form players on the ATP Tour and has carried that confidence into Roland Garros.
"I mean he's playing great," said Alcaraz of his semi-final opponent.
"It's going to be a beautiful battle, a beautiful match, I think we're both playing great tennis... it's going to be great for the people to watch as well."
The Spaniard is targeting a fifth Grand Slam title this weekend and will be a heavy favourite on Friday despite Musetti's recent good run.
Alcaraz has won the last five matches between the two since Musetti took their first meeting in the 2022 Hamburg Open final.
He also dished out a straight-sets thrashing to Musetti in the 2023 French Open last 16, losing only seven games.
World number seven Musetti will be playing in just his second Grand Slam semi-final, after a last-four defeat by Djokovic at Wimbledon last year.
Should he go through and meet Sinner for the title, it would be the first all-Italian men's final at a Grand Slam.