The incident occurred after a meet last week when another 18-year-old, Ciarra Ryan, allegedly punched Nutter and pulled her hair, the Philadelphia Inquirer said.
Police did not release many details about the incident but said there was a verbal fight that led to the assault.
Philadelphia police were called to the scene and the suspect fled, NBC News reported.
Ryan surrendered to detectives Monday and was charged with assault and recklessly endangering another person.
Lisa Nutter, Olivia's mother, told KYW-TV, Philadelphia, her daughter was involved in an incident but is fine.
Lytro unveils camera that can focus a photo after shooting it
NASA celebrates Earth Day with #GlobalSelfie