MINNEAPOLIS -- The Minnesota Vikings fear that rookie cornerback Mike Hughes tore the ACL in his left knee in Sunday's 27-17 win over the Arizona Cardinals, a league source confirmed to ESPN.

The Vikings' first-round pick is set to undergo an MRI on Monday to assess the extent of his injury. He was moving around on crutches postgame in the locker room

Hughes exited the game with 8:59 to play in the fourth quarter after his knee appeared to buckle as he dropped back into coverage against Arizona wide receiver Larry Fitzgerald.

If the early diagnosis pans out, Minnesota's cornerback depth will take a major hit. Hughes is an important depth option at outside corner, having filled in on several occasions for Trae Waynes opposite Xavier Rhodes, and the 21-year-old spent time rotating with Mackensie Alexander in the slot in Week 6.

The rookie also plays a considerable amount on special teams as the returner on kickoffs.