We had heard rumblings that Michael Bennett had been playing through an injury for most of last season, but now we have some confirmation from ESPN's Adam Schefter.
Seahaws DE Michael Bennett, who left Tampa for Seattle, was diagnosed with torn rotator cuff. Injury why Bennett got a 1-yr deal in SEA.— Adam Schefter (@AdamSchefter) March 24, 2013
Still, Bennett played last season with this injury and was still very productive notching nine sacks and becoming one of the league leaders in tackles for loss. I can't say whether this injury would be a long-term issue, since I don't have the medical expertise -- but that injury did end the career of defensive end Anthony Weaver and marked the beginning of the end for Aaron Smith, although they were both 3-4 defensive ends and were nearing the end of their careers at the time anyway.
Other players have successfully returned from that injury, though, including Drew Brees, D.J. Williams and Takeo Spikes. The injury likely played a role in Tampa's decision to let Bennett leave when he became too expensive.