The rules do not prohibit requests like Nadal’s and, despite Courier’s surprise, such requests are not without precedent. Nor are they guaranteed to succeed.

“It is not chair umpire à la carte, definitely not,” Stefan Fransson, the French Open tournament referee, said in an interview Thursday. “There is the perception sometimes that if the player just says, I don’t want an umpire, then it happens. That is not true, because if they say they don’t want this official then we find out why they don’t think they should have him, and we look into why he thinks so. We might agree. We might disagree.”

In this unusually high-profile case — which Fransson and other men’s tennis officials were reluctant to discuss in detail — there was clearly agreement within the ATP Tour, which operates independently from the four Grand Slam tournaments, that it was best for Nadal and Bernardes to take a break after Rio.

But it was also evident that putting Bernardes in the chair for a Nadal match at the French Open would do nothing more than inflame the situation.

“I don’t really want to get too specific about the case, but it would not be good for anybody,” Fransson said. “It wouldn’t be good for Bernardes. It wouldn’t be good for the tournament. It’s just too big right now. I don’t see there is any advantage to trying to do it now. I’m sure Carlos will come back with Rafa, and I think he will do that quite soon.”

As a working official, Bernardes was not allowed to comment, but Nadal said he viewed the situation as temporary.

The question is whether star players like Nadal have more clout than lower-level players.

Hard as it might be to believe, Fransson said they did not. “I think we try to treat everybody the same,” he said.