NEW YORK – There are nights when Frances Tiafoe turns Arthur Ashe Stadium into a rocking house party.

His house. His music blares from the speakers. Nearly 24,000 friends, cousins, kings, queens, stars of the screen and the dance floor, and of course half a dozen tennis stars of all time. They all dance to his beat and make every level of the large tennis court at Flushing Bay shake.

Tuesday night at the Ashe was different. No better or worse, especially because Tiafoe was advancing to the first all-American semifinal of the US Open since 2005, when Andre Agassi beat Robby Ginepri. The same party crowd filled nearly every seat, from courtside to the very top of the roof. Kevin Hart, Jason Sudeikis, Roger Federer, Sabrina Ionescu and a host of other A-list celebrities stopped by. It was the quiet end of a pulsating night turning into morning, soft jazz and R&B blaring from the speakers, glasses clinking with expensive champagne.

But the end of the evening and the 6:3, 6:7(5), 6:3, 4:1 victory that ended with an asterisk over the limping Grigor Dimitrov? It wasn’t the atmosphere. It wasn’t the walk-off that Tiafoe or his 24,000 friends had in mind.

There was already a murmur in the stadium when Dimitrov made a double fault at the end of the third set. This was nothing unusual after the second set had ended with three double faults – two for Dimitrov, one for Tiafoe – in favour of the Bulgarian.

As he sat down, Dimitrov grabbed his leg, gestured toward his team, and waved his hand through the night air as if to say, “This is it.” He looked up and smiled ruefully, unable to believe this was happening to him here and now.

He limped off the court. He limped back again. Tiafoe served out his first game of the fourth set to nil. Dimitrov hit his first serve at 84 miles per hour as he tried successfully to continue the strange, grueling tennis that had already lasted two hours and forty-five minutes.

Grigor Dimitrov retired at the end of the third set. (Charly Triballeau / AFP via Getty Images)

Things got stranger.

Tiafoe did what players often do when their opponent is struggling physically. He hit the balls straight to Dimitrov, unable to turn off the pattern play switch in his brain and move him across the court. Then he figured it out. He pulled Dimitrov into the backhand corner and formed one of those whipping, arcing cross-court forehands he hits so well, short and long. Dimitrov didn’t even move.

Tiafoe took a 2-0 lead. Dimitrov stayed on the pitch.

At 15-0, Dimitrov hit his racket on his box as if he wanted recognition for staying on the court, limping, beaten. At 40-0, Tiafoe made a double fault. He still won the match. The air had gone out of the stadium. It shouldn’t be like this.

With the score at 4-1, they were close at the net and Tiafoe was where he wanted to be. Where he was two years ago, ready to face Carlos Alcaraz and start another house party.

The whole night didn’t go like that. There were also a few moments of rising energy, like the celebratory sprint down the baseline with his racket high after Dimitrov won the first set for Tiafoe with another forehand into the net. Or when Dimitrov recovered from a lost serve in the second set with some nifty stick volleys and wrist shots that always earned him all those style points.

A few games later, Dimitrov’s legs gave way and the consequences of an agonizing five-set fourth-round victory on a sweaty Sunday took their toll. When it was over, it was a relaxing evening for the guy who throws parties like no other these days. No broken furniture. Everyone gets home safely and gets ready for what’s to come on the weekend.

Frances Tiafoe treats the US Open like no other tournament. (Charly Triballeau / AFP via Getty Images)

“I have to be more aggressive,” Tiafoe said on the court. “At the end of the day, I have to dig, dig, dig.”

“US Open semifinals, no excuses.”

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The All-American semifinal

Tiafoe’s victory over Dimitrov sets him up for a semifinal clash with his childhood friend Taylor Fritz, who defeated German Alexander Zverev in four sets on Tuesday afternoon.

Fritz and “Big Foe,” as everyone calls Tiafoe, started hitting balls at national training camps 12 years ago. Tiafoe and her other friend, Tommy Paul, were much better than Fritz back then. Fritz has flipped the script over the past three years and largely holds the title of America’s No. 1, even though Tiafoe is the bigger star.

The dry spell in American men’s tennis

For a while, Americans dominated men’s tennis. But after the fall of the Iron Curtain, the world became bigger. America’s dependence on wealth and population, which would automatically produce the best players in the world, proved to be its Achilles heel.

The USTA was late in realizing this. At the end of the 2000s, Andy Roddick was nearing the end of his career. The last American world number one and the last American to win the US Open (2003) did not have a great talent behind him.

Tiafoe and Fritz were among the first players the federation focused on when it embarked on a ten-year plan to develop players who could compete with the best. Ultimately, it took longer, as Fritz and his compatriots lost to Roger Federer, Rafael Nadal and Novak Djokovic, as well as a number of better, more consistent players from Europe over the past seven years. Then Carlos Alcaraz and Jannik Sinner came along and started beating them, too.

On Friday they have to go out and beat each other.

Andy Roddick raises the trophy in 2003. (Chuck Solomon / Sports Illustrated via Getty Images)

The story of Tiafoe’s rise and stagnation

Tiafoe has been lost for the past year, since his quarterfinal loss to Ben Shelton here 364 days ago. He thought he was destined for the semifinals and beyond. Shelton stole his lunch, grabbed the spotlight and sent Tiafoe reeling.

Since then, he has lost as much as he wins and struggled to find motivation. In July, he played his way to a third-round showdown against Carlos Alcaraz on Wimbledon’s Centre Court.

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He had never played in the cathedral of sport before and missed the eventual champion by just a few points. The crowd cheered him on like they hadn’t in a long time, reminding him why he plays this game and spurring him on to give it his all at the US Open.

“If I play well, it will definitely help the sport,” Tiafoe said.

When he saw the draw, he couldn’t look past “Ben,” his friend Shelton. Then he beat him. Then Djokovic was eliminated.

“The draw creates unrest,” he said. “And you think: why not?”

The duel

Fritz has a huge advantage. He is 6-1 in head-to-head comparisons. Tiafoe hasn’t beaten him since 2016, long before Fritz was the player he is today.

They have only played each other once at a Grand Slam, at the 2022 Australian Open, when Tiafoe fought his way out of another slump in form and began a rise that would culminate in the five-set house party against Carlos Alcaraz.

Tiafoe has the edge in terms of speed, movement and creativity. He has more shots on the court than Fritz. But Fritz has the two best shots – his serve and his forehand.

“When I first met him, he was a weird guy,” Tiafoe said of Fritz. “When we all became professionals, we pushed each other to be the best we could be. No one wanted to leave the other behind.”

Go all the way?

Two Americans in the semifinals means one will reach the final. Fritz or Tiafoe will likely have to beat world No. 1 Jannik Sinner or Daniil Medvedev, a six-time Grand Slam finalist and 2021 U.S. Open champion. No American has been in a major final since 2009, when Roddick lost 14-16 to Federer in the fifth set and the shadows fell over the Wimbledon lawn.

Medvedev and Sinner will play against each other in the quarterfinals on Wednesday. In the other quarterfinal, Australian Alex de Minaur will face Briton Jack Draper.

(Fatih Aktas/Anadolu via Getty Images)