Scott Glenn is a perfect movie cowboy. If you don't believe it, rent "Silverado," an underrated Western that never found the audience it deserved.

So Glenn's casting as a modern-day rodeo bull-rider in "My Heroes Have Always Been Cowboys" seems a natural.In addition, the supporting roles seem very well-cast - veteran Ben Johnson as Glenn's aging father, Kate Capshaw as his old flame, Balthazar Getty as Capshaw's young son who learns about rodeo riding from Glenn, Tess Harper and Gary Busey as Glenn's complaining yuppie sister and brother-in-law, Mickey Rooney as Johnson's old senile buddy, Clarence Williams III as a peace officer and Dub Taylor, Clu Gulager and Dennis Fimple as local domino-playing geezers.

But the script, by TV writer Joel Don Humphreys ("The Incredible Hulk," "The Blue Knight"), and the direction, by veteran Stuart Rosenberg, who in better days gave us "Cool Hand Luke," "Voyage of the Damned" and "Brubaker," let the cast - and the audience - down.

This is "Rocky Goes to the Rodeo," pure and simple. No cliche is left unturned, and if you can't predict the plot turns right down the line, you haven't been to very many movies.

Glenn's character has been bumming around Texas all his life, riding the rodeo circuit - mainly vicious bulls (the bull-riding sequences are the film's best moments, despite being in slow motion).

But while performing as a rodeo clown in the film's opening sequence he is injured. Still in the recovery process, he heads back to his Oklahoma hometown. Once there, he finds his father has been placed in a rest home. So he gets him out and tries to build a life for the two of them, though they've never particularly gotten along. And despite forgetful Dad nearly burning the house down with flaming bacon grease.

Glenn also tries to renew an old romance with Capshaw, whose husband was killed in an auto accident some years earlier. And he gets into a fight with a local young punk, though it doesn't lead to anything.

Eventually, Glenn learns that there is a local rodeo called Bullmania coming up, with a $100,000 prize. And wouldn't you know it - that's just what he needs to save Dad's farm!

Glenn offers a complex performance that raises the film a notch or two, and there's some genuine chemistry between him and his co-stars here, as well as some amusing moments, most of them provided by Johnson's wry performance (Rooney gets a couple of laughs as well). But most of the movie is mawkish and uncomfortable, plodding down a road that is all too familiar.

Too bad. There's nothing worse in a movie than wasted potential - and there's plenty of it here. (By comparison, another old-fashioned genre, the pirate epic, received an original injection of excitement and interest "Shipwrecked," which also opened Friday; "Heroes" could have taken a lesson or two from "Shipwrecked" on how to make an old style new.)

And in the case of Tess Harper - will this gifted actress be playing shrewish nags from now on, after being Oscar-nominated for a similar performance in "Crimes of the Heart"? Doesn't anyone remember how great she was in "Tender Mercies"?

"My Heroes Have Always Been Cowboys" is rated PG for violence, profanity and a sex scene.