As a junior, he became a full-time starter at defensive end, recording 73 tackles and 9 sacks.
Barnes was signed as an undrafted free agent by the Pittsburgh Steelers after the 1993 NFL draft.
He had 4 tackles in the eighth game against the Cleveland Browns after replacing an injured Jerry Olsavsky.
He filled in at middle linebacker in place of an injured Greg Lloyd during the fifteenth game against the Seattle Seahawks and in the playoffs.
On January 3, 1996, he was signed as a free agent by the Green Bay Packers.