After a stint in the United States Navy during World War II, Ramsey played for the Chicago Cardinals of the National Football League (NFL) from 1946 to 1951. During his time with the Cardinals, Ramsey was a member of the franchise's 1947 NFL World Championship team.
Coaching career
In 1951, Ramsey served as a player-coach for the Cardinals before becoming the Detroit Lions’ defensive coordinator in 1952. During his tenure with the Lions, Ramsey developed the 4-3 defense, a staple of modern football. In addition, he was the first coach to blitzlinebackers, in a package he called Red Dog. With Ramsey as defensive coordinator the Lions won three World Championships in the 1950s. He developed a number of Lions greats including Yale Lary, Jack Christiansen, and Jim David, among others. In 1960, he was hired as the first head coach of the American Football League's Buffalo Bills. Though fired by Bills' owner Ralph C. Wilson Jr. after the 1961 AFL season, Ramsey is credited with laying the foundation of what would become one of the best defenses in AFL history. He would go on to serve as the defensive coordinator of the Pittsburgh Steelers from 1962 to 1964.