Keys was an outstanding center and linebacker for the Western Kentucky Hilltoppers football team in 1942 and, after a stint in the military (Marine Corps) in World War II, 1946 and '47. He also lettered in baseball (pitcher-outfielder) three straight years (1946–48) after the War. He was an All-KIAC (Kentucky Intercollegiate Athletic Conference) selection in football as a senior. His 1946 baseball team went a perfect 9–0, outscoring the opponents by an average of five runs a game.
Following his career on the Hill, Keys moved north to play professional football in the Canadian Football League. He was All-Eastern Conference for three straight years (1949–51) with the Montreal Alouettes and then he earned a berth on the All-Western Conference team throughout the next three seasons while playing for the Edmonton Eskimos. He is best remembered as a player for his final game when he played on a broken leg in the Eskimos' 1954 Grey Cup triumph.
After his six years as a player, he put in six more years as an assistant coach in the CFL before being named head coach of the Eskimos in 1959. He coached Edmonton from 1959 until 1963, became an assistant coach with the Saskatchewan Roughriders in 1964 and was promoted to Head Coach in 1965. He was awarded the CFL Coach of the Year award in 1968. In 1970, the Roughriders finished with a mark of 14 wins and 2 losses, a CFL record that stood until 1989 when Edmonton went 16–2. Keys resigned at the end of that season and coached the British Columbia Lions from 1971 until partway through the 1975 season. In 1966 he won his only championship as a head coach, with his Roughriders team winning the 54th Grey Cup. As such, he was voted the All-Time All-Star Coach for the Saskatchewan Roughriders. In total, he spent 16 seasons as a head coach in the Canadian Football League.
He retired from coaching after the 1975 season and was inducted into the Canadian Football Hall of Fame in 1990. His 131 wins as a coach in the CFL still stands as the fifth highest victory total for a head coach in the league. He was elected as a builder on April 28, 1990.