Carlos Alcaraz dethroned Jannik Sinner in sensational fashion to seal his second US Open title and become new world No 1 after security delays frustrated fans.

With United States president Donald Trump in attendance, the 24,000-capacity Arthur Ashe Stadium was only about two-thirds full, while thousands of fans still were standing on the plaza outside, waiting in line to enter as the final was delayed by half an hour due to airport-style security checks.

Trump drew a mixed reaction when he was shown on screen during the national anthem, while there was loud booing when he was highlighted again at the end of the first set.

But ultimately centre stage belonged to Alcaraz, who sealed his sixth Grand Slam title with a serving masterclass, winning 6-2 3-6 6-1 6-4.

“I want to start with Jannik, it’s unbelievable what you’re doing the whole season, great level during every tournament that you’re playing… I’m seeing you more than my family,” said Alcaraz, who took his win-loss record with Sinner to 10-5.

“It’s great to share a court, to share the locker room, to share everything with you.

“I’m just really proud about the people I have around. Every achievement I’m having is because of you, thanks to you … this one is yours.”

As well as ending Sinner’s reign at the hard-court major, Alcaraz simultaneously ensured he will on Monday replace the Italian as No 1 after a 65-week reign.

Alcaraz found his groove early in his third consecutive Grand Slam final with Sinner, dictating the extended rallies to become the second youngest man to win six major singles titles in the Open Era after Bjorn Borg.

How Alcaraz won his second US Open title…

Alcaraz was marginally the form horse having arrived at the final without losing a set, while Sinner had dropped two, against Denis Shapovalov in round three and Felix Auger-Aliassime in the semi-finals, when he also needed treatment for an abdominal injury.

In most of their matches, especially at Grand Slams, there has been almost nothing to choose between them, but Alcaraz dominated the first set here, breaking serve in the opening game and running away with it.

The 22-year-old looked more dynamic, pouncing on the Sinner second serve and making very few errors, while tension was evident in his rival, who struggled to find his range.

Suddenly it was Alcaraz on the back foot at the start of the second set, with Sinner gesturing to the crowd, which finally was almost full, and then passing his opponent to secure the break.

Alcaraz had been bidding to become the first man in the Open Era to win the title here without dropping a set but Sinner ensured that statistic at least would remain.

Manchester City boss Pep Guardiola, actor Danny DeVito and singer Bruce Springsteen were among the celebrities who had flocked to Queens, and there was another twist at the start of the third set.

Two costly forehand misses from Sinner allowed Alcaraz another break and, when the Spaniard recovered from 0-30 in the next game to move 3-0 in front, he put his finger to his ear and raised his fist in the air.

That was Trump’s cue to head indoors, with the president returning to his seat only for the final stages of the contest.

This contest was quick-fire, with Sinner’s dip continuing as Alcaraz opened up a two-sets-to-one lead with less than two hours on the clock.

Sinner produced a fine volley to hold off Alcaraz at the start of the fourth set but the 24-year-old’s serve had been a weakness all tournament and it was the same story here.

The pressure was relentless and he fired a forehand long to hand Alcaraz another break in the fifth game, putting the finish line very much in sight.

Sinner fought for his crown at the last, saving two match points, but this was his rival’s day and Alcaraz took his third opportunity with his 10th ace.

“A lot of big stages and matches we played this season,” Sinner said after quickly composing himself. “I tried my best today, I couldn’t do more.”

Tale of the Tape: Alcaraz vs Sinner

Navratilova: Alcaraz practically unbeatable when on form

Sky Sports Tennis’ Martina Navratilova:

“Alcaraz just brings his best when it matters the best. He doesn’t feel the pressure against Sinner because he knows he has to play well and if he loses, it’s okay.

“Carlos has just got a slightly bigger game than Jannik, and when it cooks he is practically unbeatable.

“The numbers don’t lie, Alcaraz was better across the board.”

Henman: A ball-striking masterclass from Alcaraz

Sky Sports Tennis’ Tim Henman:

“A ball-striking masterclass. I’ve never seen Alcaraz serve like that. You think about the great servers in the game, and I now have to put Alcaraz in that category.

“Against one of the great returners [Sinner], Alcaraz’s serve was absolutely phenomenal. He was able to hit his spots with such pace and consistency.

“He gave Sinner so few opportunities to get into those service games, and it gave Alcaraz the opportunity to play with even more freedom, unleashing.

“You can see the joy of that performance. It was complete.”

Robson: Alcaraz and Sinner bringing sport to new heights

Sky Sports Tennis’ Laura Robson:

“I love that these two are such great role models for the sport. Jannik knows today he was beaten by the better player, but that will spur him on to do better in the future.

“They both lift each other in every match they play.

“In terms of shot-making, movement, physicality, they are bringing the sport to new heights.”

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