Daniil Medvedev overcomes Alex de Minaur, breathing issues en route to US Open quarterfinals 

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NEW YORK—When Daniil Medvedev isn’t beefing with the New York City crowd during the US Open, it’s usually a sign that something is up.

The Russian, famous for his contentious mid-match interactions with fans and hilarious on-court interviews, appeared to be in Low Battery mode on Monday, after dropping the first set to No. 13 seed Alex de Minaur on Louis Armstrong Stadium. A worrying exchange with the tournament doctor, in which Medvedev admitted he was struggling to breathe on an exceedingly humid evening, only added to the tension.

But the No. 3 seed quickly regrouped after receiving treatment, and won the next three sets in comfortable fashion to clinch a 2-6, 6-4, 6-1, 6-2 victory—and book a quarterfinal battle with good friend and countryman Andrey Rublev.

“Brutal match, brutal match, because of brutal conditions. So tough, so humid today,” Medvedev told press afterward. “When I practiced before the match, like usually four hours before the match, straightaway I was like, Oh, my God, it's going to be tough. It was going to be tough for everyone who was there today.

“Some people bear better with the heat, some people worse. I feel like I'm not the best one in this case. At the same time, I feel like I fight many times through it quite well, so that's kind of what happened today.”

One of the potential matchups circled by tennis watchers when the US Open draw came out last week, De Minaur trailed Medvedev 2-4 coming into their fourth-round clash. But De Minaur’s two wins came from the pair’s two most recent meetings, including a 7-6 (7), 7-5 upset last month in Toronto.

The Aussie, who said he had to play “some of my best tennis” in order to pull off the victory in Canada, looked ready to make it three in a row against the former world No. 1. Clearly struggling from the outset, Medvedev appeared sluggish and struggled to keep up as De Minaur kept him on the run.

Three games into the match, Medvedev called for the doctor and reported that he was having trouble breathing in the heavy conditions. He appeared to receive an inhaler—"I don't think it worked, because I kind of don't know how to use it," he later admitted—but ultimately dropped the opening set in just 33 minutes.

As the match went on, however, Medvedev seemed to get a spring back in his step in the second set—a stretch of the match that proved decisive, as De Minaur held off five break points early in the set before eventually dropping serve in the final game. But once the No. 3 seed found his footing, it was one-way traffic: Medvedev dropped only three more games in the next two sets to move into the quarterfinals.

"I think the turning point was second serve, I managed to serve very well till the end of the match," Medvedev said. "That gave me some air on my serve to kind of relax a little bit.

"I managed to put just a little bit more pressure on his serve here and there, then the match turned."

With the victory, Medvedev has also secured his spot at the season-ending Nitto ATP Finals—the third player to qualify after Carlos Alcaraz and Novak Djokovic.