The Champ (1979)

Billy Flynn, an ex-boxing champion, is now a horse trainer in Hialeah, Florida. He makes just enough money to raise his little son T.J., who Flynn has custody of his son after his wife Annie left him seven years ago. T.J. worships "The Champ," who has gambling debts and begins working on a comeback to give his boy a better future. Suddenly Annie shows up again and wants to become a part of T.J.'s life.