The Post cited several people with knowledge of the results.
Washington coach Mike Shanahan said Monday that Griffin will be examined Tuesday by orthopedic surgeon James Andrews to see if these are new or previous injuries.
“I'm saying right now, I really don't know," Shanahan said. "Dr. Andrews is going to take a look at Robert. A lot of times, you look at an MRI ... In my understanding, when you have an ACL injury, an LCL injury, you've had former injuries, they want to take another look -- another physical exam to make sure they're not looking at old injuries on the MRI.”
Andrews told USA Today before the game that he was "scared to death" over Griffin playing with an injured knee and a brace.
If the partial ligament tears are new injuries, the Post reported, it's unclear if surgery will be needed.
Griffin has returned from a major knee injury before -- a torn ACL he suffered in 2009 at Baylor.
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