Third seed Felix Auger-Aliassime was eliminated from the US Open in a surprising second-round loss to unseeded Russian Karen Khachanov, with the Canadian reporting he felt "dizzy and seeing spots" during the match.
Auger-Aliassime, a two-time semi-finalist at Flushing Meadows, lost 6-7 (5-7) 6-3 6-2 6-2 to Khachanov. He is the highest-ranked player so far to exit the men's singles draw.
The 26-year-old Canadian stated he began to feel unwell early in the contest. "After a set and a half, I just couldn't feel well and was dizzy and seeing spots and couldn't recover," Auger-Aliassime said. "I thought maybe it would pass, but it didn't."
He described the feeling as unusual. "I've never felt quite like that. I've had cramps before. I've felt tired towards the end of matches, but in a normal way. This was abnormal a little bit, and there were no signs in the last couple of days and no signs this morning, as well."
Temperatures in New York reached 30C on Thursday, following several days of rain. Italy's 13th seed Lorenzo Musetti also experienced physical difficulties in the conditions, falling to Australian wildcard Dane Sweeny 3-6 6-1 6-2 6-2.
These exits follow that of Novak Djokovic, the fourth seed and 24-time Grand Slam champion, who expressed strong dissatisfaction with his first-round match experience.
Auger-Aliassime had reached the quarter-finals of both Wimbledon and the French Open this year. However, he withdrew from the Rogers Cup in Montreal in August due to a back injury.
Khachanov acknowledged his opponent's condition in his on-court interview, stating, "I am not sure but maybe he had some physical issues and that is part of our sport. I wish him to feel better and speedy recovery if he is injured."