The role of Star-Lord was a career-turning role for Chris Pratt, but if he hadn't taken the role, director James Gunn knows who would have: It's Always Sunny in Philadelphia's Glen Howerton. "There was a good chance that, if I didn't cast Chris, that I would've cast Glenn Howerton in the role," The A.V. Club reported Gunn as saying in a GQ profile of Pratt.