Thigpen will join the Colts five days after he was released by the Buffalo Bills to make room for receiver Denarius Moore. He had handled much of the Bills return duties, averaging 9.7 yards on kick returns and 5.2 yards on punt returns.
Thigpen signed with the Philadelphia Eagles as an undrafted free agent out of Indiana in 2009. He has career averages of 24.3 yards and 10 yards on kick and punt returns, respectively.
Johnson signed with the Colts to back up quarterback Matt Hasslebeck after starter Andrew Luck sustained a shoulder injury two weeks ago. Johnson has been a member of seven different teams during his seven-year NFL career.