After Kobe Bryant retired from the NBA, he has gotten addicted to tennis. That addiction has led to him publishing a book about the sport, and Thursday, he visited the U.S. Open to both hype it and watch young stars Naomi Osaka and Coco Gauff.

“I played a lot of tennis, and all of a sudden, I found myself addicted to it,” Bryant said.

On Tuesday, Bryant’s Granity Studios will publish “Legacy and the Queen,” about 12-year-old orphan Legacy, an “underdog female tennis prodigy” who has to use her talents to save the magical kingdom of Nova. He conceived of the idea three years ago, found author Annie Matthew and has turned out a book that’s gotten raves from Osaka.

“Naomi’s been great,” Bryant said amidst a photo-op and tutorial with kids from a local National Junior Tennis & Learning chapter. “We got to hang out quite a bit, and I love everything she’s doing and she’s a big fan of ‘Legacy.’”

As much as Bryant loves Osaka’s run to world No. 1, he positively gushed over Gauff, a 15-year-old who beat Venus Williams en route to the fourth round at Wimbledon and is now aiming even higher.

“It’s amazing at that age to have not just the skill she possesses, but the poise,” said Bryant, noting her grit to drop Tuesday’s second set but still rally to beat Anastasia Potapova. “Dropping the first set but being able to maintain her composure, not get rattled. She goes out and performs. It’s very, very rare to find an athlete at that age to be so trusting of her skill. To be patient with it. She’s phenomenal.”

Bryant knows about being a young phenomenon. An 18-year-old high school draft pick back in 1996 who went on to make 18 All-Star games, he understands better than most the challenges of being that good that young. And he offered his sage advice on how to handle them.

“Well, I think it’s the things that come along with the success at an early age,” he said. “It’s the more commitments, more responsibilities, more opportunities, especially off the court, opportunities you have to pick and choose and weave your way through that.

“Not letting those things get in the way of her continuing to develop as an athlete, that’s the hardest thing.”

Bryant also spoke about Novak Djokovic (with whom he’s discussed the challenges of reinventing oneself as a player), Rafael Nadal (“He plays with emotion. You can see the game all over his face. I like that kind of intensity”) and his purported beef with ex-teammate Shaquille O’Neal.

After Bryant’s July 29 comment that O’Neal could’ve had 12 titles and been the greatest ever if he’d had Bryant’s drive in the gym, he shrugged, “I think people are making more about it than it is. There’s nothing that’s been said that hasn’t been said before.”