Mel Renfro was drafted by the Dallas Cowboys in the second round of the 1964 NFL Draft. Although he had won many accolades as a running back and at the time teams put their best athletes on the offensive side of the ball, Tom Landry looking to build a dominating defense decided to start him at safety. As a rookie he had an impressive season by leading the team with 7 interceptions, the NFL in both punt return and kickoff return yardage and culminated his great campaign with an invitation to the Pro Bowl. In his second year (1965), his 30 yards kick-off return average still remains as a franchise record.
In 1966 coming from an All-Pro season at safety, the Cowboys named him their starting halfback in an effort to improve its offense. He was injured in the opening game against the New York Giants and replaced by Dan Reeves, who was so impressive that Renfro was moved back to defense when he returned to action and would end up being named to the All-Pro team again.
Renfro joined the Dallas Cowboys Ring of Honor in 1981, and was elected to the Pro Football Hall of Fame in 1996. During his time with the Cowboys, even though one of his teammates was former Olympic gold medalist Bob Hayes, many experts still considered him the best athlete on the team.