Shawne Merriman has once again been shut down prematurely. The Bills placed Merriman on injured reserve today, ending his season early for the fourth time in five years.

“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,” said Bills General Manager Buddy Nix in a statement released by the team Tuesday. “So we felt it was in the best interest of our team and for Shawne to put him on IR.”

Merriman had one sack in 2011, giving him a total of, um, one sack in the calendar year that he’s been a member of the Bills.

Despite a recent history plagued by injuries and a lack of productivity, the team gave Merriman a two-year, $10.5 million contract in January. He was paid $2.5 million for that lone sack (and nine tackles) in five starts this season.

Typical of a player linked to performance-enhancing drugs, Merriman’s career started with a bang (39.5 sacks in his first three seasons), but he’s registered a grand total of five sacks since 2007. He simply can’t stay healthy, and he does not have the body of a 27-year-old.

While the Bills are likely to give Merriman a shot to play in a contract year in 2012, I’m betting that he’ll be out of the league by his 30th birthday in 2014.