"Shawne has worked extremely hard, but unfortunately, his Achilles flared back up and it doesn't appear that he will be able to return to the field anytime soon," Bills general manager Buddy Nix said in a statement. "So we felt it was in the best interest of our team and for Shawne to put him on IR."
Merriman was signed to a two-year contract last year, but injuries have hampered him.
Operating in a situational role, Merriman recorded nine tackles and one sack this season.
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