When the Colts selected Marlon Mack in the 4th round of the draft it became obvious that Frank Gore, Robert Turbin, and Mack would be the top three running backs on the depth chart. And once the signing of Christine Michael was announced, the running back depth chart seemed set for the upcoming season.
However, shortly after signing with the team, Michael was forced to the injured reserve with a fluke injury he sustained during mini camp. This injury opened the door for one of the other running backs on the roster to possibly make it on to the 53-man roster.