NEW YORK -- Novak Djokovic reached his record 47th Grand Slam semifinal, breaking a tie with Roger Federer for the most by a man, by defeating Taylor Fritz 6-1, 6-4, 6-4 at the US Open on a steamy Tuesday.
Djokovic improved to 13-0 for his career in quarterfinals at Flushing Meadows -- and to 8-0 against Fritz, an American who was seeded No. 9.
The match was played with the Arthur Ashe Stadium retractable roof partially shut, which offered shade for spectators and for the two competitors on an afternoon when the temperature topped 90 degrees Fahrenheit and the humidity was above 55%.
On the changeovers, the players sought solace by removing their shirts for a bit, wrapping ice-stuffed towels around their necks or pouring water overhead.
Both Djokovic, a 36-year-old from Serbia, and Fritz, a 25-year-old from California, had some trouble on the most sweltering day of the tournament so far.
"Very humid conditions, difficult to play for both players, but that's why we train, try to get ourselves in the best possible conditions to deliver," Djokovic said. "Not easy, but you've got to fight."
But while Djokovic eventually got his shots straightened out, Fritz's miscues just kept coming.
Fritz had 19 unforced errors and just four winners in the first set, and although he did start to put more balls in the court as the match wore on, he was unable to find the mark consistently enough. By the end, Fritz had 51 unforced errors, nearly twice as many as Djokovic's 26.
"I had the chances in the third," lamented Fritz. "I started playing some pretty good points ... I didn't take my chances."
On Friday, Djokovic will take on another American -- unseeded Ben Shelton, who took down No. 10 Frances Tiafoe in four sets later Tuesday.
It was the first time since 2005 that three U.S. men made it to the quarterfinals in New York.
Fritz heard a ton of support from the partisan Ashe fans, especially as he was trying to get back into the match against Djokovic. That seemed to hit a nerve with Djokovic, who began yelling and pumping his fists while looking into the stands when he would save a break point.
"It's expected of course that people are backing the home player and there is nothing wrong with that," Djokovic said. "I actually like the energy, like the atmosphere on center court here. Day sessions, night sessions, people are getting into it."
Reuters contributed to this story.