Former lightweight world titleholders Robert Easter Jr. and Rances Barthelemy both want another belt and they will face each other in order to try to obtain it.

Easter and Barthelemy, who is also a former junior lightweight world titleholder, will meet for a vacant secondary 135-pound title on April 27 in the main event of a Showtime-televised tripleheader (10 p.m. ET) at The Cosmopolitan in Las Vegas, Premier Boxing Champions announced on Friday.

Vasiliy Lomachenko, the pound-for-pound king and the unified lightweight world champion, holds the main belt, but Easter and Barthelemy are anxious to get their hands on another strap.

"I've wanted to fight Barthelemy since he had the lightweight title and vacated it, and now I have the chance," Easter said. "He has an awkward style and I'm up for that challenge. I am still coming in as the taller fighter with a reach advantage and I'll use it to make this fight go how I want it to. He is a former world champion and he is coming to bring it just like I am."

Easter (21-1, 14 KOs), 28, of Toledo, Ohio, won a vacant lightweight title in 2016 and made three successful defenses before being knocked down and easily outpointed in a title unification fight by Mikey Garcia in July.

Barthelemy (27-1, 14 KOs), 32, a Cuban defector fighting out of Las Vegas, won a vacant lightweight title in 2015 and made one successful defense before moving up to junior welterweight in 2017 to score a controversial decision over Kiryl Relikh in a title elimination fight. They met in an immediate rematch last March for a vacant junior welterweight title and Barthelemy lost a lopsided decision. He bounced back with a third-round knockout of Robert Frankel in December and is returning to lightweight for the fight with Easter.

"I'm looking forward to a great fight against Robert Easter Jr.," Barthelemy said. "I know I have what it takes to beat him and capture another title and become a three-time world champ. My best performances have come at 135 pounds. Both of us are former world champions who are hungry and will give the fans a sensational night of boxing. I've never lost at lightweight and that will continue on April 27."

Mayweather Promotions CEO Leonard Ellerbe is co-promoting the fight and quite familiar with both boxers.

"Two former champions looking to reclaim their championship status speaks for itself in terms of the action and will to win that Easter and Barthelemy will bring on April 27," Ellerbe said. "Both guys have already proven that they have what it takes to take care of business at this level."

The card will also feature former junior welterweight world titleholder Viktor Postol taking on Mohamed Mimoune in a title elimination fight that will put the winner in position for a mandatory shot at the 140-pound world title held by Jose Ramirez.

Postol (30-2, 12 KOs), 35, a Ukraine native fighting out of Los Angeles, is 2-2 in his past four fights, beating two obscure opponents but losing his title to Terence Crawford in a one-sided decision in a 2016 unification fight and falling to top contender Josh Taylor in a lopsided fight in last June. Mimoune (21-2, 2 KOs), 31, of France, will be making his United States debut. He has won 10 fights in a row but has not faced any top opponents.

In the opening bout, blue chip heavyweight prospect Efe Ajagba (9-0, 8 KOs), 24, a 2016 Nigerian Olympian fighting out of Houston, where he is trained by Ronnie Shields, will face Michael Wallisch (19-1, 12 KOs), 33, of Germany, in a scheduled 10-round bout.

Ajagba is coming off a second-round knockout of veteran Amir Mansour on March 9 but is best known for a fight last August when he faced Curtis Harper, who walked out of the ring after touching gloves to start the first round. Wallisch will be fighting outside of Germany for only the second time and in the U.S. for the first time. He is coming off a fifth-round knockout loss to Christian Hammer in December.