 Allen was recruited by Georgia and Georgia Tech, but he declined both offers in favor of "play[ing] for an underdog".After offering a verbal commitment to play for the Vanderbilt Commodores as a defensive lineman, Allen instead signed with Purdue, where he played as a right guard.Playing under head coach Joe Tiller and blocking for quarterback Drew Brees, Allen was a member of the 2000 team that won a Big Ten Conference championship and competed in the Rose Bowl against the Washington Huskies.