Novak Djokovic's hopes of winning another US Open title are over after Alexei Popyrin produced an inspired performance to defeat him.
Djokovic's chances of winning an unprecedented 25th Grand Slam title were boosted before the match after Carlos Alcaraz was stunned by Botic van de Zandschulp in straight sets the previous night on Arthur Ashe Stadium.
The Serbian has called his rivalry with Alcaraz beautiful for the sport, and they have immense respect for each other. However, despite several great players in the draw, his probability of winning it all undoubtedly increases with Alcaraz out of the draw.
Elements of the 37-year-old's game from the first two matches required improvement for him to compete for the title. For example, Djokovic lamented his serving performance in the last round.
Popyrin had lost to Djokovic twice in 2024. But the Australian had an extraordinary run to his first Masters-1000 title at the Canadian Open a few weeks ago, showing just how dangerous he is.
Nonetheless, Popyrin was still a considerable underdog against the four-time US Open champion. That meant the fans on Arthur Ashe Stadium were stunned by how the contest unfolded.
The 25-year-old settled straight into the match with his trademark powerful serve. Djokovic also began well on serve, and there were no dramatic moments during the opening five games of the match.
A pivotal moment of the first set came when Djokovic had a 3-2 40-0 lead on Popyrin's serve, but the Canadian Open champion dug himself out of trouble impressively, sending a message to the other end of the court that he was up for the fight.
That cost Djokovic when he produced a terrible service game by his lofty standards to get broken to love at 4-4. Popyrin secured the set 6-4, but it was still too early to think the upset was on.
Things got worse for Djokovic in the fifth game of the second set. He found himself 0-40 down again, and despite saving the first two opportunities against him, he made an unforced error on his forehand to get broken once again.
Djokovic failed to create a single chance to break Popyrin's serve, which was impeccable from start to finish in the second set. The Australian served the set out once again, and his illustrious opponent was in trouble at 4-6, 4-6 down.
However, Djokovic is widely considered the greatest player in the sport's history for a reason. He rebounded excellently in the third set, and Popyrin faltered on serve for the first time.
The 24-time Grand Slam champion broke Popyrin three times to secure the third 6-2, much to the delight of the fans on the Arthur Ashe Stadium, who made the atmosphere incredible throughout.
Djokovic had two break points in Popyrin's opening service game of the fourth but was unable to take either of them. The most incredible game of the match followed with the score at 2-2.
Both players hit extraordinary shots in the fifth game. Under pressure, Djokovic made great volleys and huge second serves, but he was bested by outrageous sliding shots from Popyrin, who eventually broke with a massive forehand.
The 25-year-old saw off another break point in the next game to go 4-2 up. To the shock of all those watching on Arthur Ashe Stadium, Djokovic's game imploded in the following service game, hitting double faults and being broken again.
Initially, the nerves got to Popyrin, and Djokovic broke to go 3-5 down. However, the Canadian Open champion made no mistake on his second opportunity. Popyrin served out a 6-4, 6-4, 2-6, 6-4 triumph, confirming another incredible US Open upset.