Liverpool - A 20-year-old man was arrested on Saturday on suspicion of a racially aggravated public order offence during Liverpool's FA Cup clash with Oldham.
Oldham player Tom Adeyemi was allegedly abused by fans during Friday's third round game at Anfield which Liverpool won 5-1.
The incident comes as Liverpool are on the defensive over the handling of the Luis Suarez affair.
Adeyemi, who is on loan from Premier League side Norwich, seemed to be in tears, and Liverpool captain Steven Gerrard moved across to the corner of the ground where the incident occurred, and comforted the 20-year-old.
Liverpool released a statement after the game in which they confirmed that police were now investigating the incident.
"An incident occurred in the second half of the match which is now being investigated by both the Club and the police," said the club statement.
"We will continue to work closely with the police to establish the details of what actually happened and will make a further statement in due course."
A report on The Guardian newspaper's website citing witnesses said Liverpool fans wearing Suarez t-shirts had racially abused Adeyemi.
The incident comes after the controversy that has raged over Liverpool striker Suarez, who was fined £40 000 ($62 000) and banned for eight matches for racist abuse of Manchester United's Patrice Evra.