Explaining why they didn’t get along, he told Elle, “James Franco is a method actor. I respect method actors, but he never snapped out of character. Whenever we’d have to get in the ring for boxing scenes, and even during practice, the dude was full-on hitting me. I was always like, ‘James, lighten up, man. We’re just practicing.’ He never lightened up.”

James later told Complex magazine, “We’ve made up, or I tried to make up with him. Maybe I was too into that role. I don’t try to be mean to anybody on a movie. In the past I’ve tended to isolate [myself], and maybe people take that as me being rude or me not liking them, but it’s really a way for me to stay in my character. I really had nothing personal against Tyrese, but I guess there were a lot of misunderstandings.”

Source: https://www.buzzfeed.com/kristenharris1/actors-hated-costars