Clayton Geathers injured his neck during the tenth game of last season against the Titans, which forced Darius Butler to move to safety.
Butler had played a majority of his eight-year NFL career at cornerback, but he made a seamless transition to safety in the second half of the year and performed very well.
The Colts were hoping to have Geathers back for 2017, but his recovery has suffered some setbacks. He has already been placed on the physically unable to perform (PUP) list for the regular season, which will keep him sidelined for at least the first six games.