Defending champion Jannik Sinner battled past 25th seed Felix Auger-Aliassime 6-1, 3-6, 6-3, 6-4 in the US Open semi-finals on Friday to book a blockbuster title clash with Carlos Alcaraz, reigniting one of tennis’s most captivating rivalries.

Earlier in the evening, Alcaraz produced a masterclass to dismantle 24-time Grand Slam champion Novak Djokovic at Arthur Ashe Stadium.

Sinner, less clinical than usual, wavered at times but ultimately held firm to secure his third straight Grand Slam final against the Spaniard.

The victory puts the Italian world number one in elite company as only the fourth man in the Open Era, after Novak Djokovic, Rod Laver, and Roger Federer, to reach all four Slam finals in a single season.

“It’s been an amazing season. The Grand Slams are the most important tournaments we have, and finding myself in another final the last one of the year, with this amazing crowd it doesn’t get any better,” Sinner said.

Reflecting on Auger-Aliassime, he added: “We played recently in Cincinnati, and he’s a completely different player now.

He served and struck the ball much better, so it was a tough match.

I noticed he seemed injured at one point, and I really hope it’s nothing serious. He’s an amazing player and person, and it’s always a pleasure to share the court with him.”

Sinner seized control early, fending off resistance in the fifth game of the opener before clinching the set as Auger-Aliassime sent a backhand wide.

From there, despite losing the second set, the Italian’s relentless intensity carried him over the line and into another showdown with Alcaraz.

Auger-Aliassime settled his nerves in his second New York semi-final, breaking for a 5-3 lead in the next set en route to levelling the match, before going toe-to-toe with Sinner in the third set, only for the momentum to shift again.

Sinner, who took a medical timeout for an unspecified issue, found his groove to close out the third set, staving off a strong challenge from his reinvigorated Canadian opponent with some clutch serving in the next set to advance.

He told reporters afterward he felt twitching in his stomach while serving at 4-3 in the second set but played down concerns about his fitness.

“After the treatment, was feeling much better,” he said.

“At some point, I didn’t feel anything anymore. I was serving back at normal pace, so it was all good.

“Nothing to worry about. But I preferred to go off court because it’s on a different spot.”

The victory set up a mouth-watering encounter with second seed Alcaraz, who saved three matchpoints in their French Open final meeting in June to retain his title before surrendering his Wimbledon crown to the Italian in July.

Sinner looked ahead to their major trilogy meeting, which will take place on Sunday, three years after the pair duelled in the New York quarter-finals in an entertaining five-setter that Alcaraz won before going on to lift the sterling silver trophy.

“I feel our rivalry started here, playing an amazing match,” Sinner said.

“We’re two different players now, different confidence too, so let’s see what’s coming. We’ve played quite a lot this year so we know each other very well.

In any case, it has been an amazing tournament, an amazing feeling to play in front of you.

“I’m looking forward to doing it again.”