John Riel Casimero cautioned those that appreciate Guillermo Rigondeaux’s style to savor their fight Saturday night.

It’ll be the last time, according to the colorful Casimero, that the Cuban southpaw will set foot in a boxing ring.

“Rigondeaux, after the fight, after August 14th, Rigondeaux will retire,” Casimero told “I’m gonna do the fans a favor and finally retire Rigondeaux.”

The 40-year-old Rigondeaux hasn’t paid much attention to the confident Casimero’s insults throughout the buildup toward their 12-round fight for Casimero’s WBO bantamweight championship. The WBA’s secondary 118-pound champion is, however, an underdog against a hard-hitting Filipino fighter who has won six straight bouts by knockout or technical knockout.

Showtime will air Casimero-Rigondeaux as the main event of a tripleheader from Dignity Health Sports Park in Carson, California.

Casimero’s trash talk aside, his promoter recognizes Rigondeaux would be by far the most noteworthy conquest on his record if Casimero (30-4, 21 KOs) wins a fight he’ll enter as a 2-1 favorite.

“Beating Rigondeaux at his natural weight, his best weight at 118, is a huge accomplishment,” Sean Gibbons, president of Manny Pacquiao’s promotional company, told “I mean, no one’s ever done it. Lomachenko had to weigh [three] divisions higher to beat up this little 118-pounder when he did it and acted like he was doing something. But this is the best pound-for-pound weight that Rigondeaux has ever fought at. So, this is a tremendous accomplishment. It’ll be great to have Rigondeaux, in his final fight, on Casimero’s record.”

Rigondeaux (20-1, 13 KOs, 1 NC), a two-time Olympic gold medalist, has lost as a professional only to Vasiliy Lomachenko (15-2, 11 KOs). The Ukrainian southpaw handled Rigondeaux relatively easily in December 2017, when Rigondeaux declined to continue following the sixth round of their fight for Lomachenko’s WBO junior lightweight title at Madison Square Garden’s Hulu Theater in New York.

An aged Rigondeaux is 3-0 since Lomachenko beat him, but Casimero seems to be his most dangerous opponent since he suffered that defeat.

“Once he feels Casimero’s power, he’s gonna go into the old mode of trying to move and trying to box,” Gibbons said. “But, you know, we all know he’s not the guy of 2013. He’ll be able to move some, but he’s gonna do a lot of backing up. He’s gonna try to counter Casimero, because once he feels that power, he’s not gonna go toe-to-toe, like he did with [Julio] Ceja. He’s gonna box more like he did with [Liborio] Solis.

“But John Riel’s IQ is tremendous in boxing. When the bell rings, he’ll figure things out and whatever Rigondeaux brings in – if he wants to go toe-to-toe, we’ve got something for that. If he wants to go run, Casimero has something for that. So, it’s a great fight because Rigondeaux is a very intelligent fighter. No one is looking past him. This guy ain’t no easy task.”

Showtime’s telecast will include another 12-round bantamweight bout between Gary Antonio Russell (18-0, 12 KOs), of Capitol Heights, Maryland, and Puerto Rico’s Emmanuel Rodriguez (19-2, 12 KOs) for the WBA interim 118-pound championship. The network’s tripleheader will begin at 10 p.m. EDT/7 p.m. PDT with a 10-round bantamweight bout in which Rau’shee Warren (18-3, 4 KOs, 1 NC), a former IBO/WBA champ from Cincinnati, is scheduled to face Las Vegas’ Damien Vazquez (15-2-1, 8 KOs).

Keith Idec is a senior writer/columnist for He can be reached on Twitter @Idecboxing.