He played in 11 games, starting nine, in 2001, recording 10 sacks, 12 tackles for loss and three forced fumbles.

Pierson started all 11 games his junior year in 2002, totaling, 32 tackles (including nine for loss), eight sacks, two forced fumbles, one interception and one blocked kick.

[2][3] Pierson was selected by the Oakland Raiders in the fourth round, with the 129th overall pick, of the 2003 NFL draft.

[1] Pierson was traded to the Chicago Bears on August 30, 2004 for an undisclosed draft pick.

[1][5] Pierson signed with the Orlando Predators of the Arena Football League on October 12, 2005.