The deal is for $1.6 million, reported MLB.com's Jim Callis. The club has not confirmed. The suggested slot value for No. 41 is $1,506,400.
Riley was listed as a third baseman upon being selected by Atlanta. Though he played shortstop this past season at DeSoto Central High School in Mississippi, he also has experience as a pitcher. He profiled more as a power-hitting third baseman type during his senior season.
The 17-year-old had made a college commitment to Mississippi State prior to reaching an agreement with the Braves.
Paul Casella is a reporter for MLB.