Serrano beat Hardy via unanimous decision in 2019, handing the American the first defeat of her professional career. Now the pair are set to clash in a rematch on 5 August.
Puerto Rican Serrano will defend the titles against Hardy in Dallas, Texas, before YouTuber-turned-boxer Paul takes on ex-UFC star Nate Diaz later in the night.
In her most recent fight, Serrano, 34, was a decision winner against Erika Cruz Hernandez in February, while 41-year-old Hardy beat Taynna Cardoso on points three weeks later.
“I’M BACK!” Serrano wrote on Instagram on Thursday (4 May). “I am the undisputed featherweight champion because Heather Hardy agreed to fight me in 2019 for her WBO title. That was the first step in my current run at featherweight.
“It’s only right that I give her the opportunity to earn it back. This will be the first time I get to fight in Texas, and I promise the fans that they will not be disappointed.”
Serrano is promoted by Paul, 26, who suffered his first defeat as a pro in February, when he was outpointed by Tommy Fury – half-brother of world heavyweight champion Tyson.
Meanwhile, fellow American Diaz left the UFC in September with a submission win against Tony Ferguson, and the 38-year-old will be making his pro boxing debut when he takes on Paul.
Diaz turned himself in to police in New Orleans last week after being charged with second-degree battery. Diaz had been filmed seemingly choking out a man in the street, and New Orleans police subsequently issued a warrant for the fighter’s arrest. Diaz later made bond.
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