LAKE FOREST, Ill. (AP) -- The Chicago Bears agreed to a five-year contract with former Oakland Raiders defensive end Lamarr Houston on Tuesday.
They also agreed to a two-year contract with former Pittsburgh Steelers and New York Giants safety Ryan Mundy and one-year deals with linebackers Jordan Senn and D.J. Williams as they try to shore up a defense that got shredded by injuries and ranked among the league's worst last season.
Chicago allowed a league-high 5.3 yards per carry - half a yard more than any other team - and tied Jacksonville for an NFL-worst with 31 sacks.
Houston started all 16 games last season for Oakland and was one of the few playmakers on a 4-12 team. He led the Raiders with a career-high six sacks and recorded 16 in four seasons with them.
Mundy made a career-high nine starts with the Giants last season after spending his first four with Pittsburgh. He had 70 tackles and a 91-yard interception return along with two pass breakups and a fumble recovery. He also had seven special teams stops.
Senn has appeared in 83 games with seven starts over six seasons with Indianapolis (2008-09) and Carolina (2009-13). He was primarily a special-teams player last season.
Williams appeared in six games and made four starts at middle linebacker last season after signing a one-year deal with Chicago. A ruptured pectoral muscle tendon cut short his season, one of several big blows on a defense that lost starters Lance Briggs, Charles Tillman, and Henry Melton for big chunks of the season. Nickel back Kelvin Hayden and defensive tackle Nate Collins also suffered season-ending injuries.
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