Carlos Alcaraz reacts to the crowd after defeating Frances Tiafoe...

Carlos Alcaraz reacts to the crowd after defeating Frances Tiafoe during the semifinals of the U.S. Open on Friday. Credit: Charles Krupa

Frances Tiafoe’s magical run in the U.S. Open ended in grueling and heartbreaking fashion Friday night.

The American from Maryland could not match the energy of Spanish teenager Carlos Alcaraz, who earned a 6-7 (6), 6-3, 6-1, 6-7 (5), 6-3 victory in a semifinal match at Arthur Ashe Stadium.

It was the third straight five-set match that Alcaraz has won en route to his first major singles final. After Tiafoe hit a shot into the net to end the match, Alcaraz dropped to the court and spread his arms and legs out in starfish fashion.

Tiafoe, who was hoping to become the first American man to make it to the final of a U.S. Open since Andy Roddick did it in 2006, got teary-eyed after he was given a standing ovation.

“I gave everything I had to Carlos. I gave everything I had the last two weeks,” Tiafoe said in an on-court interview after the match. “I felt like I let you guys down. This one really hurts .  .  . I will come back and I will win this thing one day.”

In Sunday’s final, Alcaraz will play Casper Ruud for both the title and a No. 1 ranking. Ruud defeated Karen Khachanov, 7-6 (5), 6-2, 5-7, 6-2, in the first semifinal.

“In the semifinal of a Grand Slam, you have to give everything you have inside,” Alcaraz said. “Frances gave everything on the court. This is amazing.”

Alcaraz showed no signs of fatigue from his 5-hour, 15-minute quarterfinal win that ended at 2:50 a.m. on Thursday. In fact, he was at his best down the stretch, winning four of the last five games.

Friday’s match took 4:19, a battle between two of the most popular up-and-coming young players in tennis, and there were a few times when the crowd seemed confused about whom to cheer for.

The 19-year-old Alcaraz is a star wherever he plays, but nothing has moved the needle more in this year’s U.S. Open than the play of Tiafoe, who upset Rafael Nadal in the fourth round and had won his other four matches in straight sets.

The prospect of seeing an American make it to the final for the first time in nearly two decades really brought out the stars to Arthur Ashe Stadium, among them former First Lady Michelle Obama, who exchanged a thumbs-up with Tiafoe in the first set.

Tiafoe also brought a compelling backstory. The son of immigrants from war-torn Sierra Leone, he learned to play the game at the Maryland tennis center where his father worked as a custodian.

Tiafoe should have been the more rested. He won four of his five matches in straight sets, with the only exception being his four-setter against Nadal.

Tiafoe was unstoppable in tiebreaks in the tournament. He won both his sets on tiebreaks in this match and went a record 8-0 in tiebreaks in the tournament, besting Pete Sampras’ record of 7-0 in 2000.

Ruud grinds it out

Someone forgot to tell Ruud and Khachanov that they were the undercard Friday at Arthur Ashe Stadium. That became clear when the first set of their U.S. Open semifinal match was decided with a tiebreaker that featured a 55-shot rally.

The fifth-seeded Ruud, a 23-year-old Norwegian, won both that rally and what he called the biggest match of his career, beating Khachanov in four sets. It will be the second Grand Slam final of Ruud’s career. He was steamrolled in the French Open final this year by Nadal, 6-3, 6-3, 6-0.

“After Roland Garros, I was extremely happy, but humble enough to think that could be my only final,” he said in his on-court interview. “But here I am a couple of months later.”

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