Releasing Rainey initially seemed odd as Pagano recently raved about the running back at Colts training camp. The coach said he looked like the "old Chris Rainey" from his time in high school and at Florida.
"It looked like everybody else was standing still on the tape," Pagano said about watching the running back's old film, per the team's official website. "That's what he looks like now."
The Colts signed Rainey, 26, last season, but he played in just two games as a returner.
The Colts' backfield is littered with question marks. Trent Richardson is coming off a terrible season, Ahmad Bradshaw is coming off an injury and Dan Herron currently sits as the most viable third back.