A recent MRI confirmed that Wildcats redshirt junior quarterback Clayton Thorson has torn the anterior cruciate ligament in his right knee, an injury suffered in the 2017 Music City Bowl.
Thorson will spend the next two-to-three weeks working with the Northwestern athletic training staff on prehabilitation in anticipation of a mid-January surgical repair.
There is no current timetable for his return to participation.
Thorson was an All-Big Ten selection this season as a junior, accounting for more than 2800 yards and 15 touchdowns through the air, and another eight scores on the ground. The Wheaton, Illinois, native is the winningest signal-caller in program history, and his 44 career TD passes are a Northwestern record.