With the new Arthur Ashe Stadium roof as its umbrella, action on the U.S. Open’s primary show court went on without interruption Thursday. But now there is the question of whether it is appropriate — or even possible — to put a lid on the unexpectedly loud din fostered by the roof’s $150-million superstructure.

It turns out that when Ashe is at or near its 23,771 capacity, even with the roof opened, spectator noise — including routine conversation — is amplified exponentially, to the point that the tennis etiquette of silence during play is rendered obsolete.

All four of Wednesday night’s competitors at Ashe — Rafael Nadal, Andreas Seppi, Garbine Muguruza and Anastasija Sevastova — expressed surprise at the clamor.

Nadal repeatedly scuttled his service motion and looked to the chair umpire, who kept imploring fans to pipe down. Seppi wondered if the people were “used to going to baseball and just keep talking.” Sevastova said there were times “you don’t hear the ball hit, so it’s coming to you and you think it’s still somewhere else.” Muguruza said she “didn’t feel silence at any point.”

The situation “certainly is a topic of conversation,” said U.S. Tennis Association spokesman Chris Widmaier, one that tournament officials “will be monitoring.” Perhaps, he said, there could be occasional appeals for quiet on Ashe’s huge video screens.

If players should feel some sort of formal protest is in order, they could raise complaints with their organization’s player representatives, according to Nicola Arzani, a spokesman for the men’s pro tour. Or, through their personal agents, they could address officials of the Open.

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Meanwhile, during Thursday’s Andy Murray-Marcel Granollers match, a sudden downpour on the massive Teflon roof produced the sustained roar of Niagara Falls. “Rain?” Murray said later. “Is that what that was?”

Murray was happy to be sheltered and still play. But “you couldn’t hear anything,” he said, which mattered “because we use our ears when we play. It’s not just the eyes. You know, it helps us pick up the speed of the ball, the spin on the ball, how hard someone is hitting it. If we played with our ears covered or with headphones on, it would be a big advantage if your opponent wasn’t wearing them.”

Still, racket (apart from the players’ equipment) has been a staple of the Open since it moved to its Flushing Meadows digs from Forest Hills in 1978.

Martina Navratilova used to complain that jets taking off from LaGuardia, long since diverted away from the tennis center, prevented players from judging the sound of the ball being struck. Boris Becker once said a spectator “could play the saxophone in the stands and nobody would notice.”

When Arlan Kantarian was a U.S. Tennis Association executive, he promoted the “gladiator feel” of the Open’s night sessions, which at times produced a howling-at-the-moon quality. John McEnroe campaigned to play the final at night to take advantage of the unique New York fan involvement; i.e., noise.

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It has been obvious for decades: This is not decorous (stuffy?) Wimbledon.

“The players will deal with it,” Murray said. “You get used to stuff. As an athlete, that’s what you do. We adjust to conditions.”