The U.S. Open will experiment during its qualifying rounds this year with scoreboard clocks to limit how much time elapses between points and how long pre-match warmups or mid-match clothing changes can last.

Also set to be tried out at Flushing Meadows in August's qualifying matches: letting coaches communicate with their players from the stands between points.

Depending on how the test runs go, those changes could wind up being used during the U.S. Open's main draw in 2018, according to Stacey Allaster, the U.S. Tennis Association's chief executive for professional tennis.

"We're all interested in being relevant to ... fans," Allaster said in a telephone interview Thursday. "Sports have to change."

During a meeting at the French Open, she said, the Grand Slam Board "supported trying out these initiatives" during qualifying, junior and college invitational matches in New York this year. The International Tennis Federation rules committee granted a waiver for the trials.

"We'll gather all of the results and the data and then make a determination with how we go forward for 2018," Allaster said. "The goal is to deliver our product to the fans when they tune in and to improve the flow of the competition while the fans are watching."

The USTA's plans to try time clocks and in-match coaching were first reported Thursday on the website of the British newspaper The Telegraph.

The serve clock — similar to a shot clock in basketball — would allow for 25 seconds between points, Allaster said. That's how much time players are now given on the ATP Tour, with 20 seconds the limit at Grand Slam tournaments, but those restrictions are based on each chair umpire's determination, because there aren't actually clocks visible to players or spectators on court.

The USTA took a step in this direction last year by using a 20-second serve clock on scoreboards for the U.S. Open's junior and college invitational tournaments.

Before the start of play, the clocks in New York in 2017 will dole out an 8-minute limit split up this way: 2 minutes from when players step on court until the coin toss; 5 minutes for the warmup; 1 minute until the opening point.

There isn't anything that strict governing that period now, so fans watching on TV or a mobile device can be left wondering when, exactly, a match will begin.

"We know when we turn on the television at 4 o'clock on a Sunday afternoon that there will be a kickoff for an NFL game," she said. "ESPN has asked us to have consistency with when 'first ball' is going to be" for tennis.

For breaks to return to the locker room for a change of clothing during a match, the present rule simply allows "reasonable time," so Allaster said the intention is to pick a specific number. For U.S. Open qualifying, she said, "it's probably going to be 5 to 7 or 8 minutes," with some flexibility based on how far a particular court is from a locker room.

Coaching has long been barred during matches at Grand Slam tournaments (the WTA does let coaches go to the sideline to speak to players during breaks in the action at tour events), but Allaster noted that it's often clear that communication goes on, anyway.

The idea is to bring it out into the open. From their seats in the stands, coaches will be allowed to speak or motion to their players when they're on the same end of the court — so long as they don't "interrupt the pace of play," she said.

"We know it already happens today, through signals and so forth," she said. "We know it's part of the game and we wanted to test it."

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Follow Howard Fendrich on Twitter at http://twitter.com/HowardFendrich

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