Carlos Alcaraz talks to his coach in the fourth set against Jannik...

Carlos Alcaraz talks to his coach in the fourth set against Jannik Sinner in the U.S. Open men’s singles quarterfinals at the USTA Billie Jean King National Tennis Center on Wednesday. Credit: Newsday/J. Conrad Williams Jr.

Frances Tiafoe got what he wanted.

Shortly after winning his relatively quick three-set quarterfinal match against Andrey Rublev Wednesday afternoon, the American was asked whom he would rather play Friday in the semifinals of the U.S. Open — Carlos Alcaraz or Jannik Sinner.

“I don’t really have a preference,” Tiafoe said before the two began their night session quarterfinal match. “Either guy is going to be tough. They’re both great players. I just hope they play a marathon match, super-long match, and they get really tired come Friday.

A marathon match it was.

In the second-longest match and latest-ever finish in U.S. Open history, the 19-year-old Alcaraz finally closed out the quarterfinal with Sinner at 2:50 a.m Thursday morning, winning by a score of 6-3, 6-7 (7), 6-7 (5), 7-5, 6-3. That was more than 10 hours after Tiafoe’s match ended.

All told the match lasted five hours and 15 minutes and featured countless momentum swings. The experience was so gruelingly intimate that the two fell into each other’s arms at the net at the end of the match rather than exchange the traditional handshake.

At 3:48 Thursday morning, Alcaraz was still sorting through what had happened and reached out to his opponent on Twitter. “What can I say? U.S. OPEN SEMIFINALS! Incredible battle @janniksin! You really forced me to improve, and I’m sure we’ll have many more matches in the future!”

The match was the second- longest ever played at the U.S. Open, behind only the 1992 semifinal between Stefan Edberg and Michael Chang, won by Edberg in 5 hours, 26 minutes.

The question is how the tough turnaround will impact Alcaraz when he takes on Tiafoe in a semifinal match scheduled to begin at 7 Friday night. Tiafoe’s 7-6 (3), 7-6 (0), 6-4 quarterfinal win over Rublev Wednesday afternoon took just 2 hours, 26 minutes.

It’s far from the only long match the third-seeded Alcaraz had played en route to the semifinals. In fact, it was the 19-year-old’s second consecutive five-setter as he took 3 hours, 53 minutes to defeat Marin Cilic in the fourth round on Monday. All told in his five matches, Alcaraz has spent 15 hours, 59 minutes on court and played a total of 19 sets.

Tiafoe has played a total of 16 sets and spent 14 hours, 33 minutes on the court at the Open. He’s won four of his five matches in straight sets with the only exception being his 6-4, 4-6, 6-4, 6-3 upset of Rafael Nadal in the fourth round.

“It’s going to be really, really tough,” Alcaraz said of the semifinal match. “Frances, everybody knows the level of Frances. He has beaten Rafa Nadal, Rublev in three sets. He’s playing unbelievable right now. High confidence.”

Alcaraz is a fan favorite at the U.S. Open, but he won’t be in this match.

Tiafoe, ranked 26th in the world, has become the Cinderella story of the tournament.

He is the first American man to reach the semifinals since Andy Roddick did it in 2006. Roddick went on to lose to Roger Federer in the final. Roddick is also the last American to win any Grand Slam tournament, defeating Juan Carlos Ferrero in the 2003 Open.

Alcaraz and Tiafoe have played just once before with Alcaraz winning in straight sets at the 2021 Barcelona Open.

Still, the question remains: How fast can Alcaraz recover from his grueling quarterfinal match. He doesn’t sound terribly worried.

“I felt great,” Alcaraz said in his news conference after the quarterfinal win. “Probably at the end of the match I was at my end, let’s say. It was really, really tough for me. But during the whole match, five hours, 15 minutes of match, I felt great physically.”

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