John Riel Casimero has reverted back to the original opponent for his August 14 fight date, facing Guillermo Rigondeaux after his planned bantamweight unification against Nonito Donaire Jr. fell through.

Casimero (30-4, 21 knockouts) will be making the second defense of his WBO bantamweight title, while Rigondeaux (20-1, 13 KOs) is seeking a world title in a second division after having previously reigned at 122 pounds.

“Casimero is looking forward to fighting a real fighter like Guillermo Rigondeaux, the man that beat Nonito Donaire,” said MP Promotions President Sean Gibbons. “Casimero loves fighting southpaws and will looks to become the first fighter to knock out Rigondeaux.”

The fight will take place at Dignity Health Sports Park in Carson, Calif. and will headline a Showtime Championship Boxing card.

Casimero of Ormoc City, Philippines had briefly been scheduled to face his compatriot Donaire in a WBO/WBC unification bout, but the matchup hit the rocks early on, after Donaire accused Casimero of delaying his enrollment in pre-fight drug screenings through the Voluntary Anti-Doping Agency, and then of making crude remarks against Donaire’s wife, Rachel.

Donaire, a sure-fire future Hall of Famer, said he withdrew from the fight in hopes of changing the sport’s culture, saying “I’m not going to give his example the stage or the payday that comes with it.”

Casimero, 32, won the title in November of 2019 with a third round technical knockout of Zolani Tete, and defended it last September with a third round stoppage of Duke Micah in his Showtime debut. He had previously held world titles at 108 and 112 pounds.

Rigondeaux, 40, of Miami by way of Cuba last fought in February of 2020, winning a split decision over Liborio Solis. He won the unified junior featherweight title in 2013 with a win over Donaire. He has won three straight since his lone defeat, a sixth round stoppage against Vasiliy Lomachenko.

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