The San Francisco 49ers announced Tuesday they have signed LB Blake Costanzo to a one-year deal. To make room on the roster, the team has waived G Al Netter.

Costanzo (6-1, 235) has played in 91 games over his seven-year NFL career, notching 99 tackles, five forced fumbles and five fumble recoveries on special teams. In 2013, Costanzo appeared in all 16 games for the Chicago Bears, and registered one forced fumble and one fumble recovery. After spending the past two seasons in Chicago, Costanzo returns to San Francisco where he appeared in all 16 regular season games and two postseason contests in 2011, recording 17 tackles on special teams in the regular season. He also notched four tackles, one forced fumble and one fumble recovery on special teams in the postseason.

Costanzo originally signed with the New York Jets as an undrafted free agent in 2006 and spent time with the Buffalo Bills from 2007-08 and the Cleveland Browns from 2009-10. During his time with the Browns, he was tutored by current 49ers assistant head coach/special teams coordinator Brad Seely, who coached the Browns special teams at the time.

A 30-year old native of Franklin Lakes, NJ, Costanzo played collegiately at Lafayette College and finished his career with 307 tackles, 18 sacks, three interceptions, four forced fumbles, three fumble recoveries and 12 passes defensed.

Netter was signed to the 49ers practice squad on October 14, 2013, where he spent the remainder of the 2013 season. He later re-signed with the team on January 22, 2014.