Carlos Alcaraz defeats Frances Tiafoe in five sets in the U.S....

Carlos Alcaraz defeats Frances Tiafoe in five sets in the U.S. Open men’s single semifinals at the USTA Billie Jean King National Tennis Center on Friday. Credit: Newsday/J. Conrad Williams Jr.

Sometimes, it can be hard to remember while watching Carlos Alcaraz compete at the U.S. Open that he is just 19.

He’ll hit a behind-the-back shot from the baseline — stunning enough, in itself — then gather himself seconds later to sprint forward for a backhand passing winner at the perfect angle.

He’ll get to an opponent’s drop shot, race back to retrieve the next ball by flicking it while turned away from the net, run forward to get another drop shot, then sprint back yet again to slide while somehow twisting his body for a down-the-line forehand winner — all within one point.

“I fight for every ball until it bounces twice or it’s a winner. Those points sometimes lift me up. They make me smile and I enjoy the moment,” the Spaniard said. “Every now and then, you need to create a bit of magic.”

The No. 3-seeded Alcaraz has been doing just that with regularity as he heads into a one-of-a-kind U.S. Open final on Sunday against No. 5-seeded Casper Ruud, a 23-year-old from Norway. There is so much at stake for both:

This is the first Grand Slam final between two players eyeing both a first major championship and the ATP’s No. 1 ranking.

“Of course, there will be nerves,” Ruud said, “and we will both feel it.” Ruud got a taste of this sort of stage in June, when he made it to the French Open final before losing to Rafael Nadal, a 14-time champion there. “He obviously gave me a good beating,” said Ruud, who is coached by his father, former professional player Christian Ruud. “After the final, I said, ‘If I ever reach one again, I hope it is not Rafa on the other side of the court in Roland Garros, because it’s sort of an impossible task, I think, for any player.’ I’m happy that it’s not Rafa on clay.”

That makes sense, sure. Still, taking on Alcaraz at the moment is no easy feat, either. This will mark Alcaraz’s debut on the last day of a Slam. He is the youngest man in a final at Flushing Meadows since Pete Sampras won the 1990 U.S. Open at 19, and the youngest in any major title match since Nadal won the 2005 French Open at that age.

Those two guys turned out OK: Sampras retired with 14 Grand Slam trophies; Nadal has a men’s-record 22.

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