Warren Beatty, Faye Dunaway Fought Over Who Announces Best Picture Winner

Warren Beatty gave Faye Dunaway what she demanded during rehearsal ... the honor of reading the winner of Best Picture, and he watched as she failed in spectacular fashion.

Sources who were present at Saturday's rehearsal tell us, both Faye and Warren wanted to announce the winner and went back and forth, but eventually Warren backed off and Faye got her way.

In fact, we're told their rehearsal was contentious from start to finish ... they wouldn't go onstage together to block their walkout ... they did it separately.

Watch the clip closely ... you see Faye angling to get the envelope as Warren tries to make sense of it ... as if she fears he might jack the moment and read it himself. Warren didn't warn her ... he just passed the envelope.

And watch how quickly Faye reads the winner ... it's almost as if she worried Warren would beat her to the punch. It's pretty apparent ... Warren knew something was wrong and she just jumped.

We've reached out to Faye and Warren's reps for comment ... so far, no word back.