[WATCH] Jimmy Fallon & Russell Crowe rock out to Johnny Cash on 'The Tonight Show Starring Jimmy Fallon' [VIDEO]

Put all your jokes aside about Russell Crowe's musical abilities because he, Jimmy Fallon and The Roots rocked out last night on the Tonight Show.

On the show to promote his new epic film Noah, Crowe and Fallon (on harmonica) leapt into an impromptu performance of the Johnny Cash classic "Folsom Prison Blues" aided by The Roots.

Check out the performance with the video below!