Cook got hurt in the final preseason game. Under a new league rule, a team can designate one injured player to return midway through the season if he heals. Other players put on the injured reserve list are done for the season.
Also Tuesday, the Bengals signed free-agent tight end Richard Quinn. He was Denver's second-round draft pick in 2009. The Broncos released him last August, and he signed with Washington and played in one game. He's been primarily a blocker, having only one catch in his career.
Cincinnati released tight end Bryce Davis from Central Oklahoma from its practice squad.
Copyright 2012 by The Associated Press