A Thoroughbred makes the long journey from initial training and workout to ultimate triumph as a champion horse.
| Actor | Role |
|---|---|
 Elliott LewisNarrator | Narrator |
 Jean WillesJean Trent | Jean Trent |
 Morgan FarleyGus | Gus |
| JJohnny LongdenJonnny Longden - Jockey | Jonnny Longden - Jockey |
| RRobert Scott HowardBob Howard | Bob Howard |
 William GouldTom Trent | Tom Trent |
 John BeradinoTrainer | Trainer |
 Frank DaeCol. Waldron | Col. Waldron |
 Forrest J. AckermanMan in crowd (uncredited) | Man in crowd (uncredited) |
 Russ ConwayJockey (uncredited) | Jockey (uncredited) |
| HHal J. Moore(uncredited) | (uncredited) |
| OOscar Otis(uncredited) | (uncredited) |
| JJoe HernandezRacetrack announcer | Racetrack announcer |