A 20-year-old man arrested on suspicion of racially abusing Adeyemi has been released on bail, police said on Sunday.
Gordon Taylor, chief executive of the Professional Footballers Association, said he had spoken to Adeyemi about the incident.
He said: "We can confirm that he was the victim of racist abuse towards the end of the Liverpool v Oldham FA Cup tie last Friday evening.
"This abuse came from a spectator sitting in the Kop section of the ground.
"Tom has given a full witness statement to the Merseyside police regarding the incident and will continue to assist the police fully in their enquiries."