Wilfork appeared to have injured his right foot on a light contact play. He went to the sideline, limped around, and then was ultimately carted off (and was not wearing his right cleat).
The Patriots have yet to announce anything about the injury. We'll have updates as they roll in.
If Wilfork were to miss an extended period of time, it would be a major blow for the Patriots defense. Wilfork is the defensive captain, and the anchor of the middle of the defense. With Wilfork out, the next player on the defensive tackle depth chart is undrafted rookie Joe Vellano.
Update: The New England Patriots have announced that Wilfork has left the game with an ankle injury and is questionable to return:
Injury Update from the Patriots bench: Vince Wilfork left the game with an ankle injury; his return is questionable.— New England Patriots (@Patriots) September 30, 2013