The Raiders signed free-agent linebacker Isaiah Kacyvenski on Thursday. Kacyvenski impressed the Raiders during a tryout in voluntary minicamp last month. He spent his first six NFL years in Seattle, helping the Seahawks reach the Super Bowl following the 2005 season, and was with St. Louis last season. He has started 23 games, recording 271 total tackles, one quarterback sack, and three interceptions. He has three forced fumbles and one fumble recovery. The Raiders cut defensive end Bryant McNeal and linebacker Kurt Campbell.