UFC's Bruce Buffer -- Hollywood Isn't Turning Back On Ronda Rousey

Ronda Rousey's Hollywood career is still ON THE RISE -- according to Bruce Buffer who says he's friends with a HUUGE director who has "big plans" for the UFC superstar.

Buffer -- the voice of the UFC -- says he's very close with Hollywood powerhouse Nick Cassavetes (directed "The Notebook," "Alpha Dog," "John Q.") ... and he's not turning his back on Rousey after the beating she took from Holly Holm.

Cassavetes also happens to be directing Ronda's next movie -- "Road House" -- and says he's pumped about having her star the film.

It's a pretty big endorsement for Rousey ... who's been a little "off" ever since the loss ... leading some people to question if she'll still be able to slay at the box office.

And get this ... Bruce says he MIGHT get a role in the flick, too.