LAKE FOREST, Ill. (AP) The Chicago Bears added another inside linebacker to their defense Saturday, agreeing to a three-year contract with Jerrell Freeman.

The deal with the former Indianapolis Colts player comes three days after the signing of Danny Trevathan. The moves address one of the Bears' biggest needs and give them two new starters.

The Bears also agreed to a two-year contract with defensive lineman Mitch Unrein and a one-year deal with receiver and return specialist Marc Mariani.

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The 29-year-old Freeman started all 57 games he played in the past four seasons with Indianapolis after spending three years with the CFL's Saskatchewan Roughriders.

Since entering the NFL in 2012, he is tied for sixth in tackles. He led the Colts in defensive tackles in 2012 and `13 and ranked second in 2014 and `15.

Freeman is known for his athleticism, and the Bears will be counting on that as they try to become a contender after finishing last in the NFC North at 6-10. They showed some progress in their first season under coach John Fox and general manager Ryan Pace but missed the playoffs for the eighth time in nine years.

''I wasn't really worried about the Bears' record,'' Freeman said. ''I was just looking at the pieces. And I can tell the pieces are there. I was definitely interested in Chicago from the start.''

Freeman heard good things about coach John Fox from several former teammates, particularly Colts safety and former Bronco Mike Adams. Fox also impressed Freeman when the Bears and Colts practiced together in Indianapolis last August before their preseason game, and the front office and coaches made another strong impression during their free-agency pitch.

One of Chicago's biggest areas of concern this offseason was at inside linebacker after former first-round pick Shea McClellin and Christian Jones struggled. Jonathan Anderson and John Timu got more playing time as the season wore on, but they made little impact.

Freeman said the Colts made it clear they weren't going to re-sign him, that they basically told him, ''Good luck in free agency.''

''It's a business and I guess they have other people they need to take care of. I know they've got Andrew (Luck) coming up,'' he said. ''It's a business, and I understand. From that perspective, there's no hard feelings there. I understand they've got to do what's best for their team.''

Unrein appeared in 16 games last season - two for San Diego and 14 for Chicago - and finished with 33 tackles. He played for Denver from 2011 to 2014.

Mariani is returning for his third season with the Bears. He had 22 receptions for 300 yards, 29 punt returns for 192 yards and 16 kickoff returns for 418 yards last year.

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