Chicago Bears Hall of Fame running back Gale Sayers runs upfield in a 17 to 13 loss to the Green Bay Packers on November 26, 1967 at Soldier Field in Chicago, Illinois.(AP Photo/Vernon Biever)

Gale Sayers is seen in this undated photo. (Pro Football Hall of Fame)

Gale Sayers of the Chicago Bears is shown in this undated photo. (Associated Press)

Gale Sayers, halfback for the Chicago Bears, 1967. (Associated Press)

Chicago Bears Hall of Fame running back Gale Sayers (40) runs upfield to score his first touchdown on a 80 yard run in a 61 to 20 Bears win over the San Francisco 49ers on December 12, 1965 at Kezar Stadium in San Francisco, California. (National Football League)

Gale Sayers, first year halfback of the Chicago Bear's who was named by the Associated Press as offensive player of the week for his performance in game, Oct. 19, 1965 against the Minnesota Vikings. (Associated Press)

Gale Sayers (40) of the Chicago Bears grinds out short yardage against the Green Bay Packers at the Midwest Shrine exhibition game in Milwaukee, Wis. on August 18, 1967. Sayers was brought down after gaining three yards by Packers' Bob Jeter (21). (Associated Press)

Chicago running back Gale Sayers (40) rushes headlong into Atlanta linebacker Tommy Nobis (60) in NFL game at Atlanta, on Dec. 17, 1967. Nobis stopped Sayers after a 6-yard gain in the first half. (Associated Press)

Chicago Bears' halfback Gale Sayers runs with the ball, Sept. 1968. (Associated Press)

Hall of Fame running back Chicago Bears Gale Sayers (40) runs upfield in a 21 to 42 loss to the San Francisco Forty Niners at Kezar Stadium on Dec. 6, 1969 in San Francisco. (Pro Football Hall of Fame)

Chicago Bears running back Gale Sayers carries the ball in this Nov. 10, 1970 photo against the San Francisco 49ers in Chicago. (Associated Press)

Chicago Bears Hall of Fame running back Gale Sayers (40) runs up field during game against the San Francisco 49ers, in San Francisco, Dec. 6, 1969. The 49ers defeated Bears 42-21 at Kezar Stadium. (Pro Football Hall of Fame)

Former Chicago Bears star Gale Sayers poses after his induction into the Pro Football Hall of Fame in Canton, Ohio, July 30, 1977. (Associated Press)

Former Chicago Bears running back Gayle Sayers holds a jersey during halftime ceremonies in the Bears' game with the Green Bay Packers at Soldier Field in Chicago Oct. 31, 1994. The Bears retired the uniform numbers of Sayers and linebacker Dick Butkus. (AP Photo/Fred Jewell)

Chicago Bears Hall of Fame running back Gale Sayers poses for his NFL ProLIne Profile card on April 22, 1993 in Chicago, Illinois. (National Football League)

Former pro football players from left: Gale Sayers, Joe Namath, Bart Starr and National Football League commissioner Paul Tagliabue, right, look over poster-sized illustrations of new stamps honoring legendary football coaches on the first day of issue by the U.S. Postal Service on the steps of the Pro Football Hall of Fame in Canton, Ohio, Friday, July 25, 1997. Sayers introduced the stamp of George Halas, Namath the stamp of Paul "Bear" Bryant, Starr the stamp of Vince Lombardi and Tagliabue the stamp of Glenn "Pop" Warner. (AP Photo/Phil Long)

Gale Sayers, star halfback of the Chicago Bears, sits at his desk in the brokerage firm of Paine, Webber, Jackson and Curtis is Chicago, Feb. 2, 1967. Sayers recently joined the firm's training program to become a stock broker. (AP Photo/Charles Harrity)

Chicago Bears Hall of Fame running back Gale Sayers (40) poses for a photo in Chicago, Aug. 21, 1966. (National Football League)

Gale Sayers is seen in this undated photo. (Pro Football Hall of Fame)

Gale Sayers, sensational halfback of the Chicago Bears, sharpens his eye while playing pool in his basement recreation room in Chicago, Ill., Nov. 29, 1966. Sayers was named NFL Back of the Week by the Associated Press for his recent performance against the Atlanta Falcons. A former All-American at the University of Kansas, Sayers gained 172 yards rushing on 19 carries and caught five passes for 65 yards in the Bears' 23-6 victory at muddy Wrigley Field in Chicago. (Associated Press)

Gale Sayers Kansas halfback football player, March 9, 1955. (Associated Press)

Gale Sayers, Kansas halfback in 1962. (Associated Press)

Gale Sayers, right, star running back for the Chicago Bears, and Dr. Theodore Fox, are greeted by the Bears' team mascot, a bear, as they arrive at the field for the game between the Bears and the Atlanta Falcons, in Chicago, Ill., Nov. 17, 1968. Sayers knee was severely injured last week in a game against the San Francisco 49ers. Without their star running back,the Bears lost to the Falcons, 16-13. (AP Photo/Larry Stoddard)