Riley was removed from Sunday's game against the Angels after being hit by a pitch on his right hand, Justin Toscano of The Atlanta Journal-Constitution reports.
The third baseman initially stayed in to run the bases after being struck on the hand by a 97-mph sinker in the top of the first inning, but he was replaced in the field by Luke Williams for the bottom of the frame. Riley is likely headed for X-rays, leaving his availability up in the air heading into Tuesday's series opener versus the Phillies.