TMZSports.com

Nick Jonas -- He'd Kick Justin Bieber's Ass ... Says 'Kingdom' Co-Star

Justin Bieber's career is on fire but there's still one thing he can't do ... kick Nick Jonas' ass ... that's according to Nick's "Kingdom" co-star Frank Grillo who says the JoBro's a total "badass" thanks to his MMA training.

Click here for info about our online advertising practices.