Italy’s Lorenzo Musetti reached his first semi-final at the French Open, and second at a grand slam, by beating Frances Tiafoe 6-2 4-6 7-5 6-2.

The 23-year-old will face defending champion Carlos Alcaraz for a place in Sunday’s final after the Spaniard beat Tommy Paul 6-0 6-1 6-4.

The No.8 seed was lucky not to be disqualified after kicking a ball at a line judge, however.

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In the second set against Tiafoe, Musetti kicked the ball in frustration and it hit the female line judge, standing about three metres away, in the chest.

Tiafoe looked stunned at the other end of the court and gestured towards the umpire, who eventually gave Musetti a code violation.

There were echoes of Novak Djokovic being defaulted at the 2020 US Open after accidentally hitting a female line judge with a ball.

Later, Tiafoe said: “I mean, obviously he did that and nothing happened. I think that’s comical, but it is what it is.

“Nothing happened, so there’s nothing really to talk about. Obviously it’s not consistent, so it is what it is.”

Musetti did not let the incident affect him as he moved to victory in four sets. He is now 13-4 in his French Open career, and three of those losses came against an opponent ranked No.1 — Novak Djokovic twice, Alcaraz once.

The only way he’ll need to deal with the top-ranked man again in Paris is if it’s his mate Jannik Sinner is standing across the net on Sunday with the trophy in the offing.

Musetti is one of the rare top players using the single-handed backhand, a vintage shot often praised by tennis connoisseurs.

“We are Italian, we are elegant,” he joked afterwards.

Musetti will meet Alcaraz, who steamrollered American No.12 seed Paul for the loss of five games in another one-sided night match. Paul’s right thigh was heavily strapped and he was unable to produce his best tennis.

“I’m sorry you wanted to watch more tennis. I had to do my work,” Alcaraz told the Court Philippe-Chatrier crowd.