Carlos Alcaraz wave to the crowd after defeating Matteo Arnaldi...

Carlos Alcaraz wave to the crowd after defeating Matteo Arnaldi in their fourth-round match during the U.S. Open at the USTA Billie Jean King National Tennis Center on Monday. Credit: Errol Anderson

How entertaining — despite the not-that-competitive result — was No. 1 seed and defending U.S. Open champion Carlos Alcaraz’s 6-3, 6-3, 6-4 victory over 22-year-old Italian Matteo Arnaldi on Monday afternoon?

During the under two-hour match, former Open champion Andy Roddick posted on social media: “How did we just not acknowledge that half volley that Alcaraz just hit? Was insane .  .  . like crazy great.”

Many of the commenters on Roddick’s post on X, the platform formerly known as Twitter, answered: “Which one?”

Alcaraz’s dizzying variety of shots were all on display as he defeated Arnaldi, the 61st-ranked player in the world, at Arthur Ashe Stadium.

Arnaldi said he simply couldn’t find any weaknesses in Alcaraz’s game. The 20-year-old Alcaraz appreciated the compliment.

“We try to show that to [the] opponent, try to not let him to find weakness to my game,” Alcaraz said. “I try to put him to the limit every time that I can in every match, against every opponent. I try to put my own game, try to put my style, on the match. I’m happy that he said that because I’m doing great things on the court. I try to hit the ball really clear in every match. I’m really happy with that.”

Up 3-2 in the first, Alcaraz broke Arnaldi to set up a cruise-control set victory. Alcaraz sealed it by winning all four set points on serve.

Alcaraz broke Arnaldi to open the second set and continued with a display of precision power tennis and a deft touch at the net. Alcaraz broke Arnaldi with a cross-court drop on the third set point to win the second.

Arnaldi was leading 2-1 in the third when, in a full sprint to the baseline, he chased down a ball and sent it back to Alcaraz with a no-look, overhead shot. Alcaraz blasted it back past Arnaldi to win the point.

Later in the same game, Alcaraz returned a shot from between his legs, but Arnaldi won the point, then returned to his spot to serve while making a “pump up the crowd” gesture with both arms. The crowd already was pumped up.

Alcaraz won the game on the third break point to tie the set at 2.

Later, and almost unfairly, Alcaraz wound up as if to smash a return before dropping a feather of a shot just over the net. Arnaldi chased it and, after not reaching it, ended up sprawled all over the court.

Alcaraz ended the match by taking all four points on Arnaldi’s serve.

“I’m very happy with the level that I’m playing,” Alcaraz said. “Honestly, I’ve played great matches with a great level, high quality. I hope to keep going like this.”

In the quarterfinals, Alcaraz will face No. 12 Alexander Zverev, who defeated No. 6 Jannik Sinner, 6-4, 3-6, 6-2, 4-6, 6-3, in Monday night’s late match. 

n  Rublev advances

No. 8 Andrey Rublev moved on with a 6-3, 3-6, 6-3, 6-4 victory over unseeded Jack Draper . . . No. 3 Daniil Medvedev of Russia defeated No. 13 Alex de Minaur of Australia, 2-6, 6-4, 6-1, 6-2.

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