Determine (April 7, 1951 – September 27, 1972), was an American Thoroughbred race horse. In a racing career which lasted from 1953 through 1955, the California-trained colt ran forty-four times and won eighteen races. His best season was 1954 when he became the first gray horse to win the Kentucky Derby. Determine was sired by the British stallion Alibhai a son of the 1933 Epsom Derby and St. Leger Stakes winner Hyperion. Alibhais other progeny included Your Host and Flower Bowl. Determines dam was Koubis, born with a cleft palate. Her breeder, Dr. Eslie Asbury, used specially designed instruments to repair her palate in a unique operation, but she was never raced. Koubis was a granddaughter of the mare Swing On, the dam of Seabiscuit, and was also related to Equipoise and Intentionally. Bred to Alibhai, Koubis produced a colt so small that the man who bought him for $12,000, a California automobile dealer named Andrew J. Crevolin, said he "…must have been standing in a hole when he inspected the colt." His breeder offered to take him back, but Crevolin refused, explaining that he might be letting a Kentucky Derby winner get away. The colt was sent into training with William Molter in California.