Besides chatting with Stephen Colbert during his stint as host of a public access show (and it's hilarious, which you should watch in its entirely), Marshall "Eminem" Mathers also checked in with Zane Lowe of the new Beats 1 radio station from Apple, to chat about Southpaw, the upcoming movie in which he was an executive producer. During the interview, Eminem revealed some details that you may haven't heard before.

In the inaugural Beats 1 interview on July 1, Eminem spoke about his involvement with the film, directed by Training Day director Antoine Fuqua. He wrote, recorded, and produced the film's lead single, "Phenomenal," but Eminem says he was originally suppose to star in the movie (his experience in boxing included training with legendary boxing trainer Emmanuel Steward). However, his work on his 2013 album, The Marshall Mathers LP 2, conflicted with the filming schedule and the starring role of aspiring boxer Billy Hope went to Jake Gyllenhaal instead.

"So that part sucked, but at the same I believed in the project and I wanted to do something with it," Eminem tells Lowe. "We circled back around, what if we did music for it."

My first interview for #beats1 @eminem Next week on @applemusic

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When Lowe asked if he wished his scheduled had opened up, the rapper and 8 Mile actor says, "Yeah for sure, there was a part of me that was like, 'this is crazy,' but I wouldn't change a thing about it, cause the way that Jake did it, he smashed it…the movie is incredible."

Eminem added that had he done that, it would have delayed the release of The Marshall Mathers LP 2 by a year. Between the movie and the album, he felt he needed to see the album through since he had already put so much work into it.

For the rest of the interview, Lowe and Eminem talked about the importance of the movie 8 Mile and the song "Lose Yourself" ("If there was no 8 Mile, there was no 'Lose Yourself'"). Asked if he would continue to pursue more movie roles, Eminem says, "It depends on what it is…I make music…whatever comes along that seems like it might be interesting or fun…cause at this point I just want to have fun with it…cause otherwise it's going through the motions."

The film's soundtrack will be released the same day as the film, on July 24.

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