The Cardinals signed former Chargers inside linebacker Donald Butler on Wednesday and released linebacker Quayshawn Nealy.
Butler (6-feet-1-inch and 242 pounds) played the past six seasons with San Diego after being drafted by the Chargers in the third round out of Washington in 2010. He played in all 16 games last season and made nine starts, collecting 54 tackles, one fumble recovery and one forced fumble, a half sack and five tackles for loss.
Butler, 27, could provide depth beyond starter Kevin Minter.