Exclusive | Venus Williams’ coach reveals secret to training oldest US Open player in decades, has ‘no regrets’ after legend’s ouster from tourney

Venus Williams served up plenty of history-making game this US Open.

The 45-year-old player walked into the tournament as the oldest player in the past four decades — and spent much of her three weeks on the court destroying competitors who were just half her age.

The secret to coaching a superstar? Letting her take the lead — but knowing when to tell her to take a break, her trainer, Diego Ayala, told The Post.

“When you have a player at the caliber of Venus and the pedigree of Venus, you just try to figure out what the player is looking for from a coach and tap into that,” explained Ayala, 46, a pro-trainer based out of Florida.

The pair have only been training together since June, but under Ayala’s tutelage, Williams became the second-oldest player to win a WTA Tour-level match in July.

When she arrived at the US Open last month, she also became the oldest singles player at the US Open since 1981, behind only Renee Richards, who was 47 at the time.

At 45, Williams is nearly double the age of her competitors — studies indicate that the average age of top players is between 25 and 28.

That means her training might look a little light compared to the average player.

Williams spends up to three hours a day on the court between drills and scrimmaging — and a heavier emphasis on recovery.

“Sometimes I’d have to tell her, ‘Hey, like let’s go a little easier today. You went hard four days in a row!’ I had to rein her in a little bit,” he said.

Ayala claimed there was no “secret sauce” to leading Williams to her success, but indicated that the strong relationship they built together was a major asset.

The pair came up in the tennis world at the same time — though Williams and her sister, Serena, were mega stars who “transcended the sport.”

“At first, it was kind of strange, but at the same time, I think it helped us bond a little bit better and understand each other because we are from the same era. We got a lot of the same jokes and same perspective,” Ayala said.

“If you know your stuff and she recognizes it, then she’s gonna ask for more, and so once she started asking me for more, then I’m going to give her as much as I can of myself,” he continued.

“She has the mentality, she can improve everything, all the time. So I would tap into that and help her improve the things that she already knew she wanted to do. That’s kind of how our relationship worked, and it really clicked.”

When it came to Williams’ loss Tuesday, Ayala said she was taking it well — and that the pair left “no regrets” on the court.

“One of her goals was — especially for the Open — was to enjoy herself, to embrace the challenge and the competition. And she did that with a smile on her face. So that was awesome to see,” Ayala said.