During the second set of Novak Djokovic’s historic U.S. Open victory over Daniil Medvedev on Sunday night, Djokovic, 36, was starting to show his age. Djokovic and Medvedev played a match that featured a slew of fabulous rallies—36 shots, 31 shots, 28 shots, 27 shots, 26 shots—and they appeared, at times, to be playing like two friends enjoying a hit-around at the park, except for the shots firing like rockets at one another, each man summoning the strength and concentration to return the ball over the net.

Those long points, however, cause fatigue. And Djokovic, more than his 27-year-old opponent, was breathing hard. At one point in that second set, which took a full 104 minutes to complete, Djokovic smacked his legs with his racquet, as if that would energize them. The longer this match went on, the more trouble loomed for Djokovic. Not even Djokovic, perhaps the greatest men’s tennis player of all time, can fight the physics of aging.

“I was losing air on so many occasions, and my legs, as well,” Djokovic said. “I don’t recall being so exhausted after rallies really as I have been in the second set.”

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The set went to a tiebreaker. With Medvedev holding a 5-4 tiebreak lead, Djokovic won the key point. Djokovic kept hitting the ball to Medvedev’s backhand, turning up the head on each shot, making Medvedev lean further and further to his left, until he was so off balance, he puttered a shot wide left. Medvedev couldn’t capitalize. Djokovic was then able to win the next two points to win the set. There would be no opening for the Russian.

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Only victory for Djokovic, whose 6-3, 7-6, 6-3 win over Medvedev gave him his 24th Grand Slam title, tying him with Margaret Court for the most singles majors won by a tennis player in history. What’s more, the victory finishes off a stunning transformation for Djokovic. He’s no longer a tennis heel. He’s a hero.

At the start of his run of titles, Djokovic was the cocky upstart from Serbia who crashed the Roger Federer-Rafael Nadal rivalry. Their dual domination would morph into a trio, and fervent Federer and Nadal supporters never forgave him. But now that Federer is retired, and Nadal has said he expects next year to be his last, some Djokovic haters have softened their stance. They have no choice but to admire his all-time greatness.

He also earned many critics during the Covid-19 pandemic. He created a mini-tour that spread the coronavirus in June of 2020. He refused the Covid-19 vaccine, and was deported from Australia in 2022 when he refused to comply with regulations. He could not compete in the U.S. Open last year, since he was not vaccinated. 

His stance may have been maddening for many. But it’s hard to hold it against Djokovic forever, especially now that we’re in a post-pandemic era. 

Plus, he did everything right on Sunday. In the third set, Medvedev fell on his back on the court. He lay still for a few seconds, fiddling with his elbow. Djokovic walked to the other side of the net, to offer encouragement and a helping hand. After the match, he walked into the stands and hugged his six-year-old daughter, Tara, and eight-year-old son, Stefan; credited his parents, who supported his burgeoning tennis career in the 1990s even as war raged in the former Yugoslavia; and disclosed he was wearing a t-shirt honoring his late friend Kobe Bryant (Djokovic’s major tally now matches the No. 24 Bryant wore with the Lakers).

Djokovic used a serve and volley to rattle Medvedev; in the key second set, he won an amazing 21 of 23 points at the net. Two years ago, in the U.S. Open final, Medvedev denied Djokovic a chance to become the first player to win all four major tournaments in a calendar year since Steff Graf in 1988. Djokovic shifted his mindset this time around. 

“I really did my best in the last 48 hours not to allow the importance of the moment and what’s on the line get to my head,” Djokovic said in his post-match press conference. “Because two years ago that's what happened, and I underperformed and I wasn’t able to be at my best and I was outplayed. So I learned my lesson. My team, my family knew that the last 24 hours, don’t touch me, don’t speak to me about, you know, the history of what’s on the line.”

He can do it all on the court, and is still fit and defying age. He’s now the oldest man to ever win the U.S. Open: since the start of 2021, he’s won 7 of the 10 Grand Slams in which he’s appeared. Next up for 2024: winning a 25th major, and sole possession of the all-time mark. “I'm going to keep going,” Djokovic said on Sunday. “I don't want to leave this sport if I'm still at the top.” Those cheers you heard filling up Arthur Ashe Stadium in New York—“Novak! Novak! Novak!”— may be surprising, given Djokokvic’s history. But here’s a safe bet: they’ll start to sound mighty familiar going forward.

Write to Sean Gregory at sean.gregory.com.