EVANSTON, Ill. (AP) Northwestern quarterback Clayton Thorson is questionable to return to the Wildcats' game Saturday against Penn State.

With 3:09 to go in the first quarter, Thorson was hit by Carl Nassib after completing a 13-yard pass to Christian Jones. Thorson stayed down and was taken out after suffering a lower-body injury, replaced by Zack Oliver.

Thorson entered Saturday's game with 1,119 passing yards and six touchdown passes.

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