Musicians in need of a metronome could pick up a steady beat from "The Longshots," a thoroughly conventional sports-underdog movie based on the real-life first female quarterback in the Pop Warner junior football league. The film ticks steadily through the setup about a perennial losing team, the turnaround and series of victories, the big setback, the crucial championship game.

That said, many sports movies eke tension and excitement out of this well-worn routine. "The Longshots" manages in spots as well, thanks to tightly edited games that focus solely on big, powerful payoff moments. But the few exhilarating highs can't rescue the rest of the film.

Ice Cube ("Are We There Yet?") stars as Curtis Plummer, an unemployed former football hero who never recovered from his mother's death, the accident that ended his sports career or the factory closing that gutted his small town of Minden, Ill. Then he notices that his shy, bookish, unpopular niece Jasmine ("Akeelah and the Bee" star Keke Palmer) has a surprisingly strong throwing arm. Soon he's coaching her to hit receivers by targeting posters of Beyonce Knowles and Tyra Banks; shortly thereafter, he secures her a place on the local junior football team, whose miserable string of losses keeps it from being picky about Jasmine's gender. Success on the field brings Jasmine out of her shell and Minden out of its collective funk, as the locals finally start showing some hometown pride.

The best thing about "Longshots" is Palmer, a talented young actor who brings more delicacy and depth to the material than it deserves—for instance, during a stiffly choreographed scene in which a popular girl mocks her name by offering her a toilet plunger, Palmer's vulnerable coltishness is the only convincing thing on-screen.

But even she can't get around the flat, cliche-driven script by TV writer-producer Nick Santora ("Prison Break") and "Akeelah" writer-director Doug Atchison. None of the principals talks like a person; they're all exposition machines, rigidly laying out their conflicts and dreams. The only humanity or fun in the dialogue comes from bit players who can crack jokes among themselves because they aren't too busy explaining the plot. The soundtrack is similarly unsubtle, with inspirational music prodding viewers at every turn: When Jasmine first touches a football, for instance, the swelling music stops just short of flights of angels bursting into song.

Limp Bizkit frontman Fred Durst, who made his directorial debut with 2007's little-seen "The Education of Charlie Banks," brings a workmanlike efficiency to "The Longshots" but not much style, apart from a few sequences in which he wanders away from the action to explore Minden's ragged brick streets and crumbling buildings. And even those shots seem obligatory and lacking in inspiration. It's almost always rewarding to watch an underdog triumph—what else could explain why movies exactly like this keep being made?—but "Longshots" is one underdog that's hard to love and harder still to champion.

See the trailer and find local showtimes for "The Longshots."