Trainer Chip Woolley (Skeet Ulrich) spends most of “50 to 1” on crutches while getting underdog Mine That Bird (Sunday Rest) ready for the 2009 Kentucky Derby. (Lorey Sebastian)

Watching “50 to 1,” a horse-racing drama inspired by the true story of long-shot Mine That Bird’s upset victory in the 2009 Kentucky Derby, is a lot like watching the original race — as long as you factor in about 100 minutes of pre-race television programming. As in real life, the exciting part lasts only a minute or two, and then it’s over. The rest of the movie is filler (or maybe foreplay).

How you feel about sitting through that depends on whether you’ve seen an underdog sports drama before. “50 to 1” has just about every cliche of the genre: an inconsistent athlete with more heart than wins; a coach/trainer who believes in him; and a comedy of errors leading up to the ultimate 11th-hour victory. The more boxing/baseball/ice hockey movies you’ve seen, the less appealing “50 to 1” will be.

Opening with a bar fight that reportedly represents the actual circumstances under which Mine That Bird’s trainer, Chip Woolley, and co-owner, Mark Allen, (who’s listed as a co-producer of the film) first met, the movie wastes no time in painting its central characters as lovable reprobates and cantankerous misfits.

The cadre of New Mexico cowboys responsible for Mine That Bird’s care and feeding — Skeet Ulrich’s Woolley, Christian Kane’s Allen and William Devane’s crusty veterinarian/co-owner Leonard “Doc” Blach — are a motley bunch. Woolley, the washed-up loser, believes in his horse, which chronically loses steam in the homestretch. Allen, the wealthy, boozing moneybags of the operation, believes in Woolley (for reasons that are dramatically unsupported). And Blach, the aging voice of reason, believes in neither of them.

Despite the formulaic setup, “50 to 1” manages to gin up a modicum of anticipation. Ulrich isn’t half bad as Woolley; he has believable intensity and charisma that propel the film, even when he’s required to perform such pratfalls as breaking a motel bed in half by collapsing on it. (For much of the movie, he’s on crutches. That true-life touch more or less replicates the actual indignities suffered by his character, whom TV viewers may remember hobbling into the winner’s circle with an injury incurred in a motorcycle accident.)

Even if you’ve never heard any of this back story — let alone anything about Mine That Bird — the outcome of the film is never seriously in doubt. That leaves filmmaker Jim Wilson in the predicament of having to entertain us by showing how the horse and his handlers get their act together. Unfortunately, “50 to 1” never really does that, implying that the biggest factor behind Mine That Bird’s performance in the Derby was the skill of his rider, jockey Calvin Borel, who doesn’t show up until quite late in the film.

By the way, Borel, who plays himself here, shouldn’t quit his day job.

If “50 to 1” were about 15 minutes shorter, all of this might have made for a passable diversion. As it is, “50 to 1,” much like Mine That Bird, flags before reaching the finish line.

★ ★

PG-13. At Cinema Arts Theatre. Contains some crude language, suggestive material and a bar brawl. 110 minutes.