"Jack was a tremendous player who ranked among the best in league history with his 52 interceptions while only playing in 12 games a year," Steelers Chairman Dan Rooney in a statement. "He was a versatile player who was also used as a wide receiver, but his career ended unfortunately too soon with a bad knee injury.
"He was an excellent person both on and off the field. He will be missed. Our condolences are with his family through this very tough time."
Butler, a Pittsburgh native who wasn't drafted when he came out of St. Bonaventure University, made the Steelers squad in 1951 and went on to be selected to four Pro Bowls and entered the Pro Football Hall of Fame in 2012.