If you saw Tyrann Mathieu go down with a knee injury during the Rams/Cardinals game yesterday, then you know how bad that it looked. It looked like a really serious injury, and early reports indicated that Mathieu had suffered a torn ACL. But as it turns out, it's even worse than that.

The Cardinals safety reportedly suffered a torn ACL and a torn LCL during the game, which will obviously knock him out for the remainder of the 2013-14 NFL season. But it could also knock him out of part of next season, too, and, worse case scenario, it could limit what he's able to do on the field for the rest of his career.

We obviously wish him the best and hope he has a speedy recovery. But this is devastating news for both Mathieu and the Cardinals.

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[via Pro Football Talk]