RUSSELL Crowe got Sienna Miller fired from "Nottingham?"

RUSSELL Crowe got Sienna Miller fired from "Nottingham," PAGE SIX reports.

Crowe is telling producers to get a new director and demanding script rewrites.

Miller, who was to play Maid Marian, left the movie after being "put on hold" while shooting was pushed back from February to April.

An insider said, "It is a mess. Russell never lost the weight he put on for 'Body of Evidence' - and so the love scenes between him and Sienna would have been laughable. He's so old and fat and she's so young and gorgeous. It's just . . . gross."

Producers are "looking for an older, plumper actress to play the role so [Crowe] doesn't look like a paunchy grandpa. Someone in her late 30s or early 40s." A rep for Miller - who's said to be "fine" and "about to sign onto two other movies" - declined to comment.

A studio rep acknowledged that Miller was "released" but flatly denied "these rumors" and said, " 'Nottingham' is moving ahead with Russell Crowe and Ridley Scott."