John McEnroe has questioned a tennis rule and called for a change to be implemented due to something Alexander Zverev did during the 2026 US Open final.

Zverev, who is the top seed at the US Open, is facing No 8 seed Ben Shelton in the championship match at the hard-court Grand Slam in New York.

The world No 2 is competing in his sixth Grand Slam final, and he is chasing his second major crown following his victory at the 2026 French Open.

The German made the perfect start to the match as he broke Shelton in the opening game. He broke the big-serving American again when leading 5-3 to take the first set.

Zverev’s high number of ball bounces before serving has been a talking point during the US Open, with ESPN revealing that the 29-year-old had amassed over 12,000 ball bounces at this year’s event during his quarter-final match.

Players are allowed 25 seconds from the end of the previous point before they must begin their service motion, with the shot clock started by the umpire.

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Zverev’s lengthy pre-serve routine means he often comes close to using the full time limit.

Serving at 3-3, 30-30 in the second set against Shelton, Zverev tossed the ball up and let it drop to the ground instead of serving, with two seconds remaining on the clock.

It does not count as a service fault if players abort their ball toss by letting the ball drop or catching it, providing they do not swing at the ball.

The serve clock is also stopped when a player aborts a ball toss, and there is no time limit on how quickly a player must serve after doing this.

Commentating for ESPN’s coverage of the US Open final, McEnroe argued it should be a fault if players do not serve when they toss the ball up.

“This should be over the serve clock. It was at two [seconds left] when he tossed it. Should be a fault,” said the seven-time Grand Slam singles champion and former world No 1.

Patrick McEnroe then argued that the player returning should be allowed to make the server wait when the ball is being bounced so many times.

“As a returner, when a guy’s doing this [with the ball bouncing], you should be able to step away, just before he serves,” said the former French Open doubles champion.

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