Baltimore Ravens defensive end Calais Campbell was forced to miss his team's Week 12 win against the Cleveland Browns due to a concussion. Head coach John Harbaugh spoke to reporters on Monday and revealed some crazy details about when Campbell first suffered the concussion.

Wow, that's scary. Ravens defensive end Calais Campbell suffered a concussion and both player and team didn't even know about it until a couple of days later.

Perhaps the craziest part about all this is that Ravens head coach John Harbaugh encouraged reporters to ask Campbell when he first sustained the head injury, only to inform the reporters that the star defender might not even remember when it happened.

Fortunately, it seems like it was a mild concussion for Campbell, which is good news for the Ravens. Still, it's a very scary thought to imagine suffering an injury- especially one to the head- and not remember when the injury first occurred.

The fact that the injury was reportedly minor should allow Campbell to return to the Ravens defensive line soon, perhaps as soon as in Week 13 against the Pittsburgh Steelers.

A six-time Pro Bowler, Campbell's presence should only serve to fortify a Ravens defense that smothered Browns' quarterback Baker Mayfield- and could do the same to the Steelers' Ben Roethlisberger.

However, if these crazy details about Campbell's concussion show anything, it's that perhaps the Ravens need to be a bit more careful in evaluating injuries moving forward.