David Amerson was a feel-good story for the Raiders -- right up until he wasn't. Jason Miller Getty Images

There's a reason why David Amerson hit the free agent market so late.

It's not because he's an All-Pro cornerback. It's because he struggles in coverage -- something the Raiders found out right before they replaced him with incumbent T.J. Carrie.

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Carrie (chest) returned from injured reserve-recall and played a large role (82 percent of defensive snaps) vs. the Vikings.That pushed Amerson (35 percent) down the pecking order; he played in 97 percent of them just five weeks ago.

Carrie (82 percent) stole those snaps. And it looks like he might've stolen back his old starting job in the process.

(h/t Silver & Black Pride)