Atlanta placed Riley on the 10-day injured list Tuesday with a fractured right hand.
Riley is expected to miss 6-to-8 weeks, with his regular season effectively coming to an end as a result of an injury he suffered when he was hit by a pitch in Sunday's game against the Angels. Atlanta signed Gio Urshela to take over Riley's roster spot, and he should also be in line to absorb most of the starts at third base the rest of the season.