CINCINNATI -- Just when the Cincinnati Bengals could ill afford to have their depth take a hit at receiver, they were forced Wednesday afternoon to place backup wideout Dane Sanzenbacher on the season-ending injured reserve with a concussion.

To fill Sanzenbacher's spot on the 53-man roster, the Bengals signed first-year receiver Cobi Hamilton off the practice squad.

Hamilton was on the Bengals' practice squad last season and spent time with them this preseason before he was cut just after the Bengals reached their 53-man regular-season roster limit. Hamilton then spent time on the Philadelphia Eagles' practice squad before getting re-claimed by the Bengals and signed to their practice squad prior to their sixth game.

The Bengals announced Wednesday that Sanzenbacher suffered a concussion during their 27-17 loss Sunday night at Pittsburgh. The fourth-year receiver from Ohio State had just intercepted a pass off a Pittsburgh Steelers fake punt late in the game. At the time, the pick appeared as if it would turn momentum in the Bengals' favor.

He was one of two Bengals pass-catchers to be concussed in the game. Pro Bowler A.J. Green experienced a concussion in the fourth quarter when he was hit in the head by Steelers safety Mike Mitchell after fumbling a first-down reception.

Green still is under concussion protocol. He didn't practice Wednesday.

The Bengals also were without James Wright, who spent the day rehabbing a right knee injury that has kept him out the last four games.

Sanzenbacher appeared in 10 games this season, catching nine passes for 105 yards.