The Browns have signed middle linebacker D'Qwell Jackson to a multi-year contract extension, the team announced today.

Browns President Mike Holmgren and Jackson are scheduled to meet with media at 3 p.m. today at the team's headquarters in Berea.

Jackson signed a five-year, $42.5 million deal that includes $19 million in guaranteed money and roster bonuses, a league source confirmed.

Jackson was scheduled to become an unrestricted free agent at 4 p.m. March 13, but the Browns ensured he won't hit the open market by locking him down with a new deal. The Browns could have used the franchise tag on Jackson if a contract wasn't reached, but now they won't need to do so.

The Browns still have until March 5 to franchise another one of their potential free agents. Last year, they used the tag on kicker Phil Dawson, whose contract is set to expire again.

Jackson was the runner-up for the NFL’s Comeback Player of the Year Award. He received six fewer votes than the winner, Detroit Lions quarterback Matthew Stafford.

The 6-foot, 240-pound Jackson missed 26 games -- 10 in 2009 with his first torn pectoral muscle and all 16 in 2010 with another torn pectoral -- before bouncing back and becoming the leader in defensive coordinator Dick Jauron’s 4-3 scheme last season. Jackson had a team-high 158 tackles, finishing with eight fewer than Washington Redskins linebacker London Fletcher, the league leader in tackles.

Jackson, 28, also had a career-high 3.5 sacks and three fumble recoveries to go along with an interception and a forced fumble. Jackson, whom the Browns drafted in the second round (34thoverall) in 2006, was named the AFC Defensive Player of the Month for September, when he compiled 30 tackles, a fumble recovery and a forced fumble in three games.

He was selected as a first alternate for the Pro Bowl, finishing behind Ray Lewis of the Baltimore Ravens and Derrick Johnson of the Kansas City Chiefs. He also was named the Browns’ Player of the Year by the local chapter of the Pro Football Writers of America.

The Browns finished with a record of 4-12, but their defense improved with Jackson calling the plays in the huddle and leading the team in tackles in all but three of its games. In 2011, the Browns ranked 10th in defense (332.4 yards allowed per game) and fifth in points allowed (19.2 per game) after ranking 22nd (350.1 yards allowed per game) and 13th (20.8 points allowed per game) in those respective categories the previous season.

Jackson played last season under a one-year contract worth about $4.5 million, including incentives. At the end of this past season, Jackson expressed his desire to re-sign with the Browns because they didn't give up on him after he endured two season-ending injuries.