Clark played college football for the Penn State Nittany Lions, earning All-American honors.
He was the fourth pick overall in the 1980 NFL draft, but chose to play for the CFL's Toronto Argonauts before joining the NFL's New Orleans Saints and Kansas City Chiefs.
The Green Bay Packers selected Clark in the first round (fourth pick overall) of the 1980 NFL Draft, but he refused to play for them, and instead joined the Toronto Argonauts of the CFL.
[2] He later played a single season for the World League of American Football's Barcelona Dragons.
Clark started all ten games and was co-leader in sacks with seven that season.