The future of boxing in Brooklyn faces an uncertain future now that billionaire Joe Tsai is officially the new owner of the Nets and Barclays Center. His takeover has triggered the resignation of Brett Yormark, who built Barclays Center into one of the top four boxing venues in the country.

Tsai, a Taiwanese-Canadian businessman, bought the Nets and the arena for a reported $3.37 billion. Yormark, the CEO of parent company BSE Global, will oversee the transition before leaving his position. A successor has yet to be named.

Yormark oversaw the Nets’ transition from New Jersey to Brooklyn, but also fiercely supported the addition of boxing to Barclays Center’s entertainment programming. The venue has hosted 36 shows in the seven years since its opening, including the first world championship fight in Brooklyn in 81 years.

“It’s been a heck of a run,” Yormark told The Post. “I’ve accomplished just about everything I wanted to here. We’ve truly built a world-class sports entertainment company. We transformed the Nets brand to a championship-contending type team. The Barclays Center has become destinational and global. Thanks to ownership support, I was able to do it and now it’s time to usher in a new personal chapter for myself. I’m really excited about it.”

Whether the new ownership group is as committed to boxing as the former ownership remains uncertain. Yormark doesn’t anticipate much of a change because boxing generally is enjoying a bit of revival, catering to the network and live-streaming markets.

“Our team that supports the boxing program is still in place,” Yormark said. “They see the value of it. New ownership sees the value of it. Boxing is on the rise. You can see it. Major media platforms have boxing as part of their conversation now.”

It will be tough to match Yormark’s passion for the sport. He initially ruffled local boxing promoters by signing an exclusive deal with West Coast-based Golden Boy Promotions. Gradually, local promoters and area fighters were groomed and featured in Barclays bouts, leading to nights featuring Bernard Hopkins and Danny Garcia from Philadelphia; Paulie Malignaggi, Daniel Jacobs and Luis Collazo from Brooklyn; as well as world-class talent from other parts of the country such as heavyweight champion Deontay Wilder. But it was Yormark’s alignment with Premier Boxing Champions that created a consistent schedule of quality fights. Yormark still serves as the chairman of the advisory board for PBC.

The new overseer of boxing at Barclays will have to navigate the sometimes volatile waters that come with the sport and negotiating bouts. Friends can become quick enemies and then become friends again.

“Brett and his team did a fantastic job of building a broad-based sports entertainment brand,” said Stephen Espinoza, the general manager and president of Showtime Sports. “But anybody who knows Brett knows, boxing was one of his personal passions. That has been the impetus for the rebirth of boxing in Brooklyn. To come in and do 36 boxing shows in just under seven years is a level of commitment to the sport that no other venue in North America and maybe in the world has shown.”

There was grumbling that some of the bouts lacked appeal, and ticket sales weren’t always as good as publicized. The consistency, nevertheless, has helped create renewed interest in the sport, especially in a borough where great fighters such as Mike Tyson and Riddick Bowe were born.

“Regardless of which fighters you’re a fan of, boxing fans always had something to look forward to,” Espinoza said. “And that consistency in the programming is what really makes Barclays Center a go-to destination for boxing fans. There always seems to be something coming up on the calendar.”

Yormark said the departure of Russian billionaire Mikhail Prokhorov and his business partner Dmitry Razumov prompted him to resign.

“They’ve become family to me and I could never have seen myself continue here without them,” he said, adding he will make a decision “sometime next month on where I’m looking to go.”

Boxing only can hope Yormark’s successor is as passionate about the sport as he is.