Following a collegiate career with the Arkansas Razorbacks, in 1952 Hanner was drafted by the Green Bay Packers of the National Football League (NFL), for whom he started at defensive tackle.

Hanner's streak of 28 consecutive years associated as a player or coach of the Packers is second in team history to that of legendary player-coach Curly Lambeau.

He started at left defensive end in 1961 and 1962 for the team's first two National Football League championships under head coach Vince Lombardi.

[7] "I just felt the decision had to be made because we weren't getting the total effort from our defense," head coach Starr told the media following the surprising termination.

"[7] A nine-year teammate of Starr's, Hanner was regarded as the head coach's closest confidant on the staff and was taken aback by the firing.

[12] After being in poor health for an extended period, Hanner suffered a heart attack and died two days later on September 11, 2008, at the age of 78.