Johnson played college football for the University of Texas, and was a two-time unanimous All-American.
A first-round choice in the 1980 NFL draft, he played professionally for the Los Angeles Rams and Seattle Seahawks.
In his final three seasons he was a member of a team that placed among the nation's top-ten in total defense.
That year his fourth-down tackle inside the Texas five-yard line preserved a win over Oklahoma.
In an era before the advent of the Thorpe Award, Johnson was named the nation's top defensive back of 1978 by the New York Downtown Athletic Club.