Nadal added: “I’m telling you this with some type of sadness, because I don’t want to have any problems. But this umpire is, I think, trying in a certain way to look for my faults, my errors. This is the impression I have.”

In the same interview, Nadal said of Ramos, “I respect him a lot.”

Active chair umpires are generally not permitted to give interviews because of tour policies. Ramos has not spoken publicly about Saturday’s match, in which Williams called him “a thief” for assessing the violations and also accused him of sexism, saying he had dealt with her more harshly than he would have a male player in the same circumstances.

“I’ve seen other men call other umpires several things,” she said after the match. “I’m here fighting for women’s rights and for women’s equality and for all kinds of stuff. For me to say ‘thief’ and for him to take a game, it made me feel like it was a sexist remark. He’s never taken a game from a man because they said ‘thief.’”

But he has not been hesitant to penalize men. Ramos gave Murray a code violation during the 2016 Olympics after Murray accused him of “stupid umpiring.”

“No sexist issue there,” said Chris Evert, the former world No. 1, on Sunday. “His history with men players shows that.”

Although Ramos has officiated more men’s matches during his career, he also has now officiated at three of the four women’s Grand Slam singles finals: the French Open in 2005, Wimbledon in 2008 and now this year’s United States Open, where he also officiated in women’s semifinal matches in 2014 and 2016. (Williams played in four of those matches.)

On Saturday, Mouratoglou admitted that he had been giving signals to Williams, although she said she did not see them. Mouratoglou also said that the current rule banning coaching during Grand Slam tournaments (it is allowed in WTA Tour events) was a gateway to “hypocrisy” because coaching was so widespread despite the rule. In its statement Sunday, the WTA said coaching should be allowed across the sport.