Don Cook was born in Winnipeg and attended the University of Manitba, though at the time there was no football program at the university.  Cook did play hockey for the U of M Bisons and got his first taste of football at age 20 with the St. Vital Bulldogs intermediate team.

 In 1959, Cook joined the Hamilton Tiger-Cats B team which played at the Intermediate level for two seasons (1958-59) while he worked at Stelco.  Tiger-Cat coach Jim Trimble liked what he saw in the young tackle and signed him for the big team in 1961. Cook played two games for the Tiger-Cats and was waived in October to make room for future Hall of Famer Tommy Grant who was returning from an injury. Cook was claimed by Saskatchewan, but declined to report to them the following season and that ended his professional football career.