Harrington played college football at Jackson State, where he rushed for 2,132 yards and 26 touchdowns.
In his rookie season, he suffered hamstring and thigh injuries and was limited in games.
In 1981, head coach Dick Vermeil expected Harrington to compete for the starting fullback position and occasionally play halfback.
[2] In 1982, Harrington again was expected to compete for the starting fullback job with Hubie Oliver and Leroy Harris.
On September 21, 1984, Harrington was given a tryout for the Miami Dolphins, who needed to replace injured running back Andra Franklin.