Slayton is sitting out Wednesday's training-camp session due to a hamstring injury that is thought to be minor, Ralph Vacchiano of SportsNet New York reports.
The rookie fifth-round pick watched from the sidelines while the Giants held their first practice of camp. Once he gets on the field, Slayton will join a deep competition for the No. 3 job at wide receiver, battling Corey Coleman, Cody Latimer, Bennie Fowler and Russell Shepard.