Originally set at New Line, Lionsgate has now acquired Warrior, which is a mixed-martial-arts saga about two estranged brothers on a collision course to fight in a tournament for the heavyweight championship.
O'Connor wrote the script with A.M. Tambakis and Cliff Dorfman, and he will produce with his brother, Greg O'Connor.
The director conceived the drama as a potential trilogy, and Lionsgate will also be involved in a mixed-martial-arts tournament dubbed Sparta that will be launched in connection with the movie.
O'Connor has partnered in the 16-man grand prix tourney project with UFC heavyweight champion Randy Couture, who will play himself in the film.
Casting for Warrior has begun, which is set to shoot January in Mexico and Pittsburgh.