Keenan Allen's had a rough go with injuries for his entire football career, dating back to college. Last year he suffered a lacerated kidney that kept him out of half the season. And this year he's not off to a great start, getting carted off after suffering a non-contact knee injury against the Chiefs Sunday.

In the first half of a stunning Chargers performance, Allen fell to the ground and rolled around in pain while grabbing his knee after a non-contact injury away from the play.

He was carted off the field, obviously in distress, appearing to cry as he made his way back into the locker room.

Allen's dealt with a ton of injury issues and it's not difficult to speculate about what might be the issue -- non-contact knee injuries are oftentimes ACL situations, which would be devastating to a Chargers offense that had high expectations this season.

Allen was quickly ruled out by the Chargers, not a good sign either.

We'll update this post as we know more but you can check in with our live blog as well to get the details as they emerge.