Top Rank has finally made official what has been in the works for some time -- it signed light heavyweight world titleholder Artur Beterbiev to a promotional deal, and he will defend his belt for the second time against "Hot Rod" Radivoje Kalajdzic.

The fight will headline the Top Rank Boxing on ESPN card on May 4 (ESPN/ESPN Deportes, 10 p.m. ET, with the full undercard on ESPN+ beginning at 6:30 p.m. ET) at Stockton Arena in Stockton, California.

Junior bantamweight world titlist Jerwin Ancajas will make his seventh defense in the co-feature when he takes on mandatory challenger Ryuichi Funai.

Beterbiev's signing took time to formally announce because of the long-standing legal issues he has had with former promoter Yvon Michel. But that relationship was finally and officially severed on Monday when the fighter and promoter announced they had terminated their promotional deal and also ended all of their legal proceedings.

"I am relieved and happy to now be able to focus 100 percent on my training and my performances in the ring," said Beterbiev, boxing's only world titlist with a perfect knockout percentage. "I want to thank Yvon and all members of the GYM team for their efforts and support in developing my career since arriving in Canada in 2013."

Light heavyweight world titleholder Artur Beterbiev will put his championship on the line against Radivoje Kalajdzic on May 4. Mikey Williams for Top Rank Boxing

Beterbiev, a two-time Russian Olympian, moved to Montreal after the 2012 Olympics and turned pro under Michel's guidance in 2013. Michel said time and again that Beterbiev was the best prospect he had ever signed, but their relationship eventually soured. The legal fight over Beterbiev's contract led to him having only one fight in 2017, when he won a vacant title, and one fight in 2018.

Michel wished him well in his new deal.

"In the last few months it has become clear to us and Artur that a solution negotiated in good faith would be preferable to the consequences of a prolonged judicial debate," Michel said. "We are proud of the work accomplished with Artur during our association and we wish him the best success in the pursuit of his career."

Now Beterbiev (13-0, 13 KOs), 34, moves on to Top Rank, which is loaded with top opponents for him to face in the future. Top Rank also promotes world champion Oleksandr Gvozdyk and super middleweight titlist Gilberto "Zurdo" Ramirez, who is moving up to light heavyweight, and co-promotes light heavyweight titlist Sergey Kovalev and former titlist Eleider "Storm" Alvarez (with Michel).

First up, however, is the dangerous Kalajdzic (24-1, 17 KOs), 27, a Bosnia native fighting out of Saint Petersburg, Florida.

"I am very excited to defend my IBF light heavyweight title on May 4 against a high-quality opponent like Radivoje Kalajdzic," Beterbiev said. "This will be a great fight, and I can't wait to get in the ring and show once again why I am the best 175-pound boxer in the world."

Kalajdzic's lone defeat was a highly controversial eight-round split decision in 2016 to Marcus Browne, who now holds an interim light heavyweight belt. Kalajdzic has won three fights in a row since.

"I'm thrilled to get this opportunity to challenge for a world title against a great fighter like Artur Beterbiev," Kalajdzic said. "It will be a very exciting fight. Both of us hit hard, so expect fireworks. I am focused on securing a victory and will take full advantage of this shot. A win opens so many doors for me and will change my life. On May 4, the light heavyweight division will have a new world champion."

Top Rank is putting the card on against one of the biggest fights of the year, the middleweight unification bout between Canelo Alvarez and Daniel Jacobs. But the company was left with little choice. It promised Beterbiev, who survived a knockdown in a fourth-round knockout victory over Callum Johnson in an October shootout, he would be back in the ring before he begins observing Ramadan, which starts on May 5. May 4 was the only available date for Top Rank to give Beterbiev a fight before then.

Ancajas (30-1-2, 20 KOs), a 27-year-old southpaw from the Philippines, will have his fourth fight in a row in the United States. He is coming off a draw with Alejandro Santiago in September.

"I was hard at work three weeks after my last fight with Santiago," Ancajas said. "I am going to be in the best shape in my upcoming fight with Funai. Coming off my last fight, I really want to give a great performance and defend my world title in style for the fans in Stockton and everyone watching on ESPN."

Funai, 33, of Japan, a pro since 2005, will be fighting outside of his home country for the first time and facing his first top opponent.

"I am excited for this opportunity to challenge for a world title and to make my professional debut in America," Funai said. "I know I have the experience and the skills to become the new IBF champion of the world. Jerwin and I respect one another, but this is boxing, and I am going to fight my heart out."

The card will also include lightweight prospect Gabriel Flores Jr., a Stockton native with a fan following. Flores (12-0, 5 KOs), who was 16 when he signed with Top Rank, will face Eduardo Pereira (23-9, 19 KOs), 29, of Brazil, in a six-round bout three days before he turns 19.

"I was born and raised in Stockton, and it is the city I still call home. To get the opportunity to fight at the big arena in front of my friends, family, and biggest fans is a dream come true," Flores said. "This is only the beginning of my journey. One day, I will fill up that arena as a world champion. I am excited to use my platform to show kids that bullying is unacceptable and that we must treat everyone with dignity and respect."