sentences:  He also recruited Abner Haynes and Leon King to North Texas in 1956, where the pair eventually broke the color barrier for college football in the state of Texas the next season.His second to last recruiting class in 1965 included future NFL Hall of Famer Joe Greene, who went on to become the only All-American in North Texas football history, and a four-time Super Bowl champion with the Pittsburgh Steelers.After Mitchell left in early 1967, North Texas had just one conference title and three winning seasons over the next six years.