Defensive back Brian Jackson was promoted from the practice squad to take Johnson's place on the roster.
A seventh-round draft pick in 2007 out of Arizona, Johnson started 14 games last season. He played the first two games this season, then was inactive last week.
Jackson is an undrafted rookie out of Oklahoma. He originally signed with the New York Jets and played in all four of their preseason games before being waived Sept. 7.
Copyright 2010 by The Associated Press