DEMECO RYANS - A two-time Pro Bowler, Ryans was acquired to be the answer to the question that has long loomed over middle linebacker. He has the pedigree, but has to bounce back from a down season in 2011.

JAMAR CHANEY - After a fast start as a rookie, Chaney had a rocky 2011, starting at the strong side and then moving to the middle early in the season. He struggled at times, and will have to move back outside with Ryans in town.

BRIAN ROLLE - Rolle was probably the team's most effective linebacker last season, and showed impressive power for his size. But he is generously listed at 5-foot-10, and his height is a concern.

CASEY MATTHEWS - He rebounded from a disastrous start to contribute in pass coverage late last season, but Matthews still has to improve against the run. A full offseason may help him and Rolle after last year's lockout.

MOISE FOKOU - The strong-side linebacker lost his starting job and missed the end of the season with an ankle sprain. He'll be fighting for a roster spot.

KEENAN CLAYTON - The fourth-round pick in 2010 has intriguing speed, but the Eagles don't seem to have a defined role for the former safety.

AKEEM JORDAN - He started seven games at linebacker, but performed best on special teams.

GREG LLOYD- Injured in training camp, he spent most of 2011 on the practice squad and was inactive once added to the roster.

MONTE SIMMONS - He signed after he spent all of 2011 on the 49ers' practice squad. He has yet to play in an NFL game.

- Jonathan Tamari