John Riel Casimero was able to make amends with Nonito Donaire, though his next conversation will have to be with another bantamweight in his future.

The reigning World Boxing Organization (WBO) bantamweight titlist has been ordered to enter negotiations with Paul Butler for a mandatory title fight. The sanctioning body contacted both camps on Wednesday, with talks due to begin immediately as to avoid a purse bid hearing.

“The WBO World Championship Committee hereby orders the parties herein commencement of negotiations for the above-mentioned WBO Bantamweight Mandatory Championship Contest,” Luis Batista-Salas, chairman of the WBO Championship Committee informed the promoters for both parties via official letter, a copy of which has been obtained by “Please be advised that the parties have twenty (20) days upon receipt of this letter to reach an agreement.

“If an accord is not reached within the time frame set forth herein, a Purse Bid will be ordered pursuant to WBO Regulations of World Championship Contests.”

Casimero is promoted by MP Promotions, whose president Sean Gibbons was copied on the alert. Paul Butler fights under the MTK Global banner, represented by Lee Eaton in ordered talks.

Philippines’ Casimero (31-4, 21KOs)—a three-division titlist—has held the WBO bantamweight title since a third-round knockout of Zolani Tete in November 2019. Just two defenses have followed, a third-round knockout of unbeaten Duke Micah last September and a twelve-round decision win over long-reigning lineal junior featherweight titlist and current bantamweight contender Guillermo Rigondeaux this past August in Carson, California.

The fight with Rigondeaux was scheduled earlier this spring, only for hopes of replacing the fight with a unification bout versus Donaire (41-6, 27KOs) shortly after the Fil-Am superstar captured the WBC title. The two initially agreed to terms for an August 14 clash, only for Donaire to remove himself from the mix due to a breakdown in drug testing procedures along with claims of misogynistic comments directed at wife/manager/trainer Rachel Donaire from Casimero’s camp.

Donaire was left without a fight, while Casimero proceeded with the originally scheduled clash with Rigondeaux which proved tough on the eyes. Casimero offered an apology earlier this week to Donaire, who accepted the olive branch.

It didn’t, however, come in time to revisit talks for a year-end clash.

Butler (33-2, 15KOs) briefly held the IBF bantamweight title in 2014, vacating the title in pursuit of a shot at a junior bantamweight title. The Cheshire, England native came up short in a March 2015 bid versus Tete who held the IBF 115-pound title at the time. Nine wins followed before dropping a twelve-round decision to then-unbeaten Emmanuel Rodriguez in their May 2018 vacant IBF bantamweight title fight.

Butler, 32, has since won his last seven starts. In his most recent appearance, Butler claimed a ten-round decision over Willibaldo Garcia this past June in Bolton, England. The victory positioned him as the number-one contender to Casimero’s crown.

The deadline for current ordered talks is October 12, at which point a purse bid hearing will be called by the WBO. Either side can request the fight go to purse bid at any point during the negotiation period. Should it reach that point, the fight will be made available to all WBO-registered promoters, provided they meet or exceed the $100,000 minimum bid limit.

Jake Donovan is a senior writer for Twitter: @JakeNDaBox