Joaquin Phoenix shocked his co-star Mark Wahlberg on the set of new movie We Own The Night - by mercilessly making fun of veteran actor Robert Duvall.

No subject was off limits for Phoenix when it came to mocking 76-year-old Duvall, including his baldness.

Wahlberg says, "Every day I'm telling Joaquin, 'Hey, be quiet!' He called Duvall a dinosaur, he said, 'Look at your head - it's peeling!' He was non-stop."

And Duvall admits he got annoyed with Phoenix on a couple of occasions, although he still thinks the 32-year-old is a "great guy."

Duvall says, "I got really ticked a couple of times."

(This news article provided by World Entertainment News Network)