“I was thinking, one of the best matches I ever saw,” Berrettini said in an on-court interview. “I was playing, but I was watching also.”

Berrettini is part of a new wave of Italian male players that includes Marco Cecchinato, who is ranked 66th in the world and made the semifinals of the French Open last year, and Lorenzo Sonego, No. 49 . All of them are 26 or younger, and 11th-ranked Fabio Fognini, 32 , is playing the best tennis of his career. Each is looking to become the first Italian man to win a Grand Slam singles title since Adriano Panatta won the French Open in 1976.

Right now Berrettini has the best chance, but he may have to rein in his nerves, which were on display when he double-faulted on his first match point — at 5-3, 40-30, of the fifth set. He failed to convert on three more match points, as Monfils kept reaching deep to extend the contest to its limit.

Finally, at 6-5 in the tiebreaker, Monfils hit a return long off a 125-mile-per-hour serve, and Berrettini collapsed on the court. He then jumped up and ran to the net to shake hands with Monfils, pounding his chest as he went.

Defeated players are not known to pound their chests, but Monfils would have been justified in doing so, considering how much heart he, too, showed in the match. Instead the Frenchman slapped Berrettini’s hand at the net, and the two competitors hugged in mutual appreciation.

“What a great fight,” Berrettini said. “I have to say congrats to Gaël.”