John Riel Casimero is back to the opponent he planned on facing all along.

The August 14 edition of Showtime Championship Boxing has reset back to its originally announced headliner, as Casimero will defend his WBO bantamweight title versus former lineal junior featherweight champion Guillermo Rigondeaux at Dignity Health Sports Park in Carson, California. News of the bout was confirmed to BoxingScene.com by Sean Gibbons, president of Manny Pacquiao’s MP Promotions who handles Casimero’s career.

Rigondeaux (20-1, 13KOs) re-entered the mix after initially being replaced by four-division and reigning WBC bantamweight titlist Nonito Donaire, who has since withdrawn from the fight.

The development comes on the heels of allegations from Donaire and wife/manager/trainer Rachel Donaire of Casimero (30-4, 21KOs) not responding in time to alleged repeated requests to submit paperwork to enroll in random drug testing as conducted by Voluntary Anti-Doping Agency (VADA). The claims came days after it was reported that Donaire (41-6, 27KOs) would replace Miami’s Rigondeaux to create a true unification bout on August 14, marking Showtime’s first boxing telecast on the other side of the upcoming Tokyo Olympics.

Donaire officially entered the mix on June 19, three weeks after returning to the title stage following a fourth-round knockout of unbeaten WBC bantamweight titlist Nordine Oubaali (17-1, 12KOs). Just six days later, however, Donaire went public insisting that he was no longer going through with the fight. The declaration came following a recorded dispute with a member of Team Casimero over a series of misogynistic remarks directed at Rachel Donaire.

VADA confirmed that Casimero’s team was officially contacted by its office on the morning June 25, with paperwork for enrollment received early afternoon June 26. A little more than three hours after receipt of paperwork, VADA publicly acknowledged that both boxers were enrolled in the program.

Testing was suspended on June 27 upon the discovery that the bout was no longer officially scheduled.

Hope was held out for the WBC/WBO unification bout to proceed, only for Donaire issue a public statement to unequivocally state that he was not moving forward with the fight. The future Hall of Famer also spoke to changing the culture in the sport, taking a stand against misogyny and other level of disrespect that blatantly crossed the line of general trash talk.

The good news was that Rigondeaux was always on board to take the fight and is once again back on the schedule rather than settling for an undercard spot. The Cuban southpaw brings to the table a secondary version of the WBA title which he claimed in a 12-round win over Liborio Solis last February in Allentown, Pennsylvania.

Casimero attempts the second defense of the title he claimed in a third-round knockout of Zolani Tete in November 2019. His lone ring appearance since then came last September, when he stopped previously unbeaten Duke Micah inside of three rounds as part of a Showtime Pay-Per-View event.

The title defense versus Micah came five months after he saw a three-belt unification versus WBA/IBF titlist Naoya Inoue (21-0, 18KOs) fall through. The two were due to collide last April, only for the coronavirus pandemic to cancel those plans.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox