Mario Sean Clark (born March 29, 1954) is an American former professional football player who played as a cornerback for the Buffalo Bills and San Francisco 49ers[1] in the National Football League (NFL).

He played college football at the University of Oregon.

[2] While playing with the Bills, Clark recorded 25 NFL interceptions by the age of 27.

Clark won a Super Bowl championship in 1984 as a member of the San Francisco 49ers in Super Bowl XIX.

This biographical article relating to an American football defensive back born in the 1950s is a stub.