Chuck Liddell is psyched he got to film with the Kelce brothers ... telling TMZ Sports that, despite their enormous fame, Travis and Jason are super humble dudes!
We saw the retired MMA superstar at the L.A. premiere for "Kill Me Again," (directed by ex-MMA fighter turned actor Keith Jardine, who we also spoke to!), just days after we got behind-the-scenes footage of Liddell kickin' ass (literally) in the Kelce's Garage Beer short film.
LIGHTS, CAMERA, ACTION!