The senior entered the game under center after Thorson threw his second interception of the game.
Following Clayton Thorson's second interception of the game, with Northwestern tied at 14 in the third quarter with Purdue, senior Zack Oliver replaced the redshirt freshman for the Wildcats' ensuing drive after a Purdue punt.
There was no noticeable injury that Thorson suffered which would allow us to think the substitution was health-related but we cannot be sure if the move was solely performance-based. Oliver completed his first two throws of the possession, one a 13-yard pass to Mike McHugh and the other a 37-yard toss to Solomon Vault.