Johnson, who hasn't thrown an NFL pass since 2011, became expendable when Cincinnati selected former Alabama standout A.J. McCarron in the fifth round of this past weekend's draft. The Bengals also signed veteran signal-caller Jason Campbell earlier in the offseason to serve as the backup to returning starter Andy Dalton.
The soon-to-be 28-year-old has started five career games, all coming during his four-year stint with Tampa Bay from 2008-11, and thrown for 1,042 yards with five touchdowns and 10 interceptions.
Among Cincinnati's undrafted free-agent signings were Stanford tight end Ryan Hewitt, Texas guard Trey Hopkins and Florida State running back James Wilder, Jr.