In October 2019, Castillo lost on points to WBA ligh heavyweight champion Dmitry Bivol. He returned in July 2021 in the Dominican Republic, defeating Ronald Gonzalez.
As a reminder, the stakes of Canelo's December clash against Smith were the British WBA super-middleweight belt and the vacant WBC belt in the same category. Canelo dominated the fight and won by unanimous decision, solidifying himself as the world boxing star.
Callum Smith returns in a new weight class with a new trainer, James "Buddy" McGirt, an American specialist, once world champion in two divisions and then the trainer of many champions, in recent years known primarily for his collaboration with Sergey Kovalev.