Calla Kessler/The New York Times
Roger Federer and Ashleigh Barty strode toward the weekend at the United States Open dogged by a question.
Were they still suffering from the Wimbledon blues?
Federer, the men’s No. 3 seed and an eternal fan favorite, arrived at his third-round match on Friday after a pair of error-laden performances in which he’d looked uncharacteristically weary.
At age 38, after reaching the Wimbledon final in July only to lose an epic marathon to Novak Djokovic, did Federer have a hangover?
And what about Barty, the second-seeded woman?