With just over seven minutes left in the first half, and Purdue leading 28-14, junior cornerback Ricardo Allen had the first of back-to-back pick-sixes that ended up being the difference in the game.
With Marshall in a shotgun, three receiver formation, Purdue lined up in a nickel 3-3-5 stack with man coverage. The 3-3-5 package is a passing down package that features three defensive linemen, three linebackers and five defensive backs.
The play was designed for tight end Bryan Attaway to run an inside streak to clear the safety out of the post route receiver Tommy Shuler ran underneath. As Shuler cut to the middle, he bumped Attaway, which gave Allen enough time to undercut the route. A bad pass from Marshall quarterback Rakeem Cato sent the ball right into the hands of Allen, who then returned the interception 38 yards for his fourth career score, setting a Purdue record.