EVANSTON, Ill. -- Northwestern quarterback Clayton Thorson has a torn anterior cruciate ligament in his right knee, throwing his future up in the air.
The school said Tuesday he will work with the athletic training staff to prepare for surgery in mid-January. There was no timetable for his return.
Thorson announced last month he would return for his senior season. He was then injured catching a pass on a trick play during a win over Kentucky in the Music City Bowl on Friday. Thorson came up clutching his right knee after being tackled and left the field on a cart.
Coach Pat Fitzgerald said after the game that the preliminary exam indicated no serious injury. Subsequent tests revealed the tear.
Thorson's 27 victories are the most by a Northwestern starting quarterback. He ranks second on the school's all-time list in yards passing, completions and total offense.
The Wildcats (10-3) hit the 10-win mark for the second time in three years and posted bowl victories in back-to-back seasons for the first time. Their 2018 opener is at Purdue on Aug. 30.
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