Don Cox was a standout football player at Hamilton high school. He was named team captain his senior season with the Aggies. He would graduate from the University of Alabama before embarking upon his coaching career. Cox's first head coaching opportunity came at Brilliant in 1972.

Cox stayed there for three seasons before taking over at Dora for another five years. In 1980 he accepted the head coaching position at Russellville.

His Russellville teams reached the finals twice in 1987 and 1992 only to come up short both times. In 1987 they lost a heart-breaker to Greenville 20-21 and in 1992 fell to Blount 29-15.

In 23 season his career coaching record stands at 180-73-4 at three different schools. His teams won 10 area and region championships with a 57-22 record.

His playoff record in 12 appearances is 20-12. Three of his teams finished the regular season undefeated. Between 1985 and 1988 Russellville had a regular-season winning streak of 32 games.

Cox also served as assistant principal, principal and administrative assistant for the Russellville City Board of Education. Cox served on the AHSAA District 7 Board and Central Board, including a term as president.

Coach Cox is a member of the Marion County Athletic Hall of Fame and coached in the Alabama-Mississippi All-Star Classic in 1992. He was named Coach of the Year by the Alabama Sports Writers in 1992. In 2008 he was inducted into the Alabama High School Athletic Associations Hall of Fame.