Raiders middle linebacker Nick Roach, who led the club in tackles a season ago, was placed on injured reserve on Wednesday, the club said.

The 29-year-old Roach has not played in the regular season after suffering a concussion in Oakland’s third exhibition game. He notched 112 tackles and 5.5 sacks in 16 starts for the Raiders in 2013. He had played the previous seven seasons with Chicago (2007-2013). Miles Burris has moved in at middle linebacker in Roach’s absence.

In a corresponding roster move Wednesday, the Raiders signed fifth-year linebacker Jamar Chaney, who spent time with Denver in the preseason. The 27-year-old Chaney has recorded 158 tackles in 45 regular season games in stints with Philadelphia (2010-2012) and Atlanta (2013).

via Mike Wilkening of ProFootballTalk