Bears' Grasu suffers 'fairly serious' knee injury

Chicago Bears center Hroniss Grasu suffered a right knee injury during Saturday's practice session and was carted off the field.

The extent of Grasu's injury wasn't revealed but head coach John Fox was concerned.

"I don't know the extent of it," Fox said to Rich Campbell of the Chicago Tribune. "It looked fairly serious."

Grasu incurred the injury after blocking downfield on a passing play, and went down without contact.

"It was non-contact. He was changing direction and it didn't go well so we'll see the extent of it as we go," Fox said via Zach Zaidman of CBS2 Chicago.

If Grasu is out for a prolonged period, Ted Larsen is expected to start at center.

Grasu was selected in the third round of the 2015 NFL Draft out of Oregon.