Source: Hernandez to have MRI Monday

Patriots tight end Aaron Hernandez will have an MRI on his right ankle on Monday, according to a league source.

Hernandez injured the ankle early in the first quarter of the team's 20-18 loss to the Arizona Cardinals on Sunday. He was escorted to the locker room area by members of the team's medical staff, and did not return. After the game, Hernandez left the stadium with the assistance of crutches and wearing a walking boot.

It remains unclear at this time how long the injury will keep Hernandez out.