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Strange details surround Lions CB Mathis' concussion diagnosis

Dec 16, 2013; Detroit, MI, USA; Detroit Lions cornerback Rashean Mathis (31) tackles by Baltimore Ravens wide receiver Marlon Brown (14) during the second quarter at Ford Field. Mandatory Credit: Andrew Weber-USA TODAY Sports

Dec 16, 2013; Detroit, MI, USA; Detroit Lions cornerback Rashean Mathis (31) tackles by Baltimore Ravens wide receiver Marlon Brown (14) during the second quarter at Ford Field. Mandatory Credit: Andrew Weber-USA TODAY Sports

It took an inordinately long time for the Lions to diagnose Rashean Mathis with a concussion. Andrew Weber USA TODAY Sports

Detroit Lions cornerback Rashean Mathis finds him at the center of a strange situation involving the late detection of a concussion.

On Wednesday, the team announced that Mathis is going through concussion protocol, per Dave Birkett of the Detroit Free Press. The injury likely stems from contact sustained during a Week 7 loss to the Minnesota Vikings, but he sat out during the team's trip to London before the bye with an "illness" -- not specifically diagnosed as a concussion.

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Lions head trainer Kevin Bastin detailed how Mathis' mysterious passing of the original screening process, followed by days of headaches without an official diagnosis (h/t Free Press):

Our game against the Vikings, he had an episode where he got hit late in the game. We took him inside with our team physician and the unaffiliated neuro-specialist on the sideline. And he was examined, taken through the whole -- all the testing process, and it was determined that he did not have a concussion.

Came in the next day for our typical day here on Monday, still no symptoms. Completely clear. We traveled to London, he woke up Thursday morning with a light headache, as he described it, and those were his only symptoms. He practiced light on Thursday and Friday, and then woke up Sunday morning with those headaches again. So we'd determined to keep him out of the game. And then when we got back here last week, he still had light headaches, we had him evaluated again by our team doctors and the independent neurologist and we decided to put him in the concussion protocol. So that's going to be the process with Rashean this week.

This story is certainly outside the norm, if not to say strange. The NFL has such a heightened awareness for head injuries now that it's hard to understand how Mathis' concussion went undiagnosed for as long as it did. It's also difficult to imagine a 35-year-old veteran of the league not being able to recognize his symptoms and communicate them to the training staff sooner than he did.

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