The terms of the deal remain undisclosed. The Colts waived running back Brandon Radcliff in a corresponding move.
Michael, 26, split his season with the Seattle Seahawks and Green Bay Packers in 2016, rushing for 469 yards and six touchdowns in nine games with the Seahawks, adding 20 receptions for 96 yards and a score. But the Seahawks cut him in Nov. 2016 after Thomas Rawls returned from injury and rookie C.J. Prosise impressed the team early in the season.
The Packers signed him shortly thereafter, and he rushed for 114 yards and a touchdown in six games with the Packers. The team then re-signed him in March before cutting him and fellow running back Don Jackson on May 1 after drafting three running backs in this year's NFL draft.
Michael has always tantalized with obvious talent but has never quite lived up to the hype, though he was solid for the Seahawks last season. Still, Michael isn't a feature back in the NFL. Rather, he's a nice option to use in a platoon situation, a role the Colts likely envision him filling.
Frank Gore will likely remain the starter, while Robert Turbin is solid in short-yardage situations and rookie Marlon Mack has big-play potential.
Nonetheless, Michael will have the opportunity to prove he can handle a larger role than a mere depth option in Indianapolis. If he can replicate his play with the Seahawks, he should at least see a decent amount of touches in 2017.