None. The refinement that he needs had to begin at an early age (an age before he even started Boxing). He is a former champion in his 30s and a late bloomer to boot. He also has little intuitive Boxing sense. To add to that, from what I know of AJ's temperament, switching trainers would leave him even more timid, stiff and unsure of himself and his Boxing. He should stick with what he knows.
Isnt going to help him though. He needs to bully Usyk and have stamina to go long emough to get him out of therevor bag enough rounds. AJ is weird to me in a way cause he seems confident yet unsure of himself and like he is hiding a dark side yet he fights like he doesnt have that dog in him.
Only the cruel tutelage of Pai Mei will give AJ the skills to vanish Lord Usyk: This content is protected