Mackey appeared in all 11 games for the RiverHawks in 2008, collecting 15 total tackles and one tackle for loss.  His effort in the classroom was rewarded with a selection to the Lone Star Conference North Division Commissioner's Honor Roll.

Mackey appeared in seven games as a true freshman for the RiverHawks in 2007.  He collected seven tackles on the year and will be competing for a starting job this season. 

An All-Conference and All-Star selection for the Lions as a prep senior, Mackey also was an Oil Bowl participant.