Serbian tennis star Novak Djokovic, one of the greatest to ever play the game, was upset at the U.S. Open Friday night. Djokovic fell in the third round with a 6-4, 6-4, 2-6, 6-4 loss to 28th-seeded Alexei Popyrin of Australia.

No. 2 seed Djokovic’s loss came just one night after No. 3 seed Carlos Alcaraz, who entered the U.S. Open as the favorite to win the tournament, was defeated in the second round.

“It was just an awful match for me,” Djokovic said. “I wasn’t playing even close to my best. It’s not good to be in that kind of state where you feel OK physically, and of course you’re motivated because it’s a Grand Slam, but you just are not able to find your game. That’s it. The game is falling apart, and I guess you have to accept that tournaments like this happen.”

CARLOS ALCARAZ UPSET IN SECOND ROUND AT US OPEN BY BOTIC VAN DE ZANDSCHULP IN STRAIGHT SETS

Novak Djokovic, of Serbia, shakes hands with Alexei Popyrin, of Australia, during a third round match of the U.S. Open tennis championships, Friday, Aug. 30, 2024, in New York. (AP)

Djokovic had sought to become the first player in tennis history with 25 Grand Slam singles titles. But he instead completed a year without claiming at least one major championship for the first time since 2017. Before then, 2010 was the last time he finished a year without a major championship.

This year marks the first season since 2002 that Djokovic, Rafael Nadal and Roger Federer did not win a Slam trophy.

Djokovic’s third-round exit matches his worst showing at Flushing Meadows, with the only other times he was beaten that early at the U.S. Open coming in 2005 and 2006.

US OPEN PLAYER THAT LOST TO COCO GAUFF ADMITS TO NAPPING BETWEEN MATCHES

Novak Djokovic, of Serbia, reacts against Alexei Popyrin, of Australia, during a third round match of the U.S. Open tennis championships, Friday, Aug. 30, 2024, in New York. (AP)

He has reached the final in Arthur Ashe Stadium 10 times, and won the title in 2011, 2015, 2018 and 2023.

However, on Friday, he double-faulted 14 times and appeared physically sluggish and emotionally flat. This comes after securing his first Olympic gold medal for Serbia by beating Alcaraz in the final at the Paris Games earlier this month.

“Obviously, it had an effect,” Djokovic said. “I spent a lot of energy winning the gold, and I did arrive to New York just not feeling fresh mentally and physically. But because it’s the U.S. Open, I gave it a shot and I tried my best. I mean, I didn’t have any physical issues. I just felt out of gas. And you could see that with the way I played.”

Alexei Popyrin, of Australia, reacts against Novak Djokovic, of Serbia, during a third round match of the U.S. Open tennis championships, Friday, Aug. 30, 2024, in New York. (AP)

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Popyrin will now attempt to reach his first Grand Slam quarterfinal, after beating Djokovic, as he looks to defeat No. 20 Frances Tiafoe, who outlasted No. 13 Ben Shelton in an all-American match that lasted 4 hours, 3 minutes on Friday evening.

“If he serves well, plays well, he can beat anybody,” Djokovic said about Popyrin. “Look, Alcaraz is out. I’m out. Some big upsets. The draw is opening up.”

The Associated Press contributed to this report.