PORT Adelaide forward Jeremy Finlayson has admitted to making a homophobic slur towards an Essendon player in Friday night's win at Adelaide Oval.

As AFL.com.au reported earlier on Saturday, the AFL will now investigate the incident after the comment was picked up by the on-field umpires' microphones and called out by Bombers teammates.

As the incident was detected through the umpire microphones, the League will run its process through the integrity unit.

In a statement on Saturday night, Port Adelaide confirmed that Finlayson had told the club of the incident during the three-quarter time break and apologised to the unknown victim after the siren.

"A contrite Finlayson made the club aware during the three-quarter time break and apologised to the victim on field after the final siren last night," the statement read.

"Finlayson, who will be counselled by club leaders in the coming days, will provide a statement tomorrow.

"The club will now wait for the AFL to complete its investigation."

AFL spokesperson Jay Allen earlier confirmed the League was aware of the incident and was investigating.

"We are aware of an alleged comment made by a Port Adelaide player in last night's match vs Essendon. We are taking this matter extremely seriously," he said.

"AFLIU (AFL integrity unit) are now investigating and we will provide an update once that investigation is completed."

Finlayson kicked three goals from 19 disposals in Port's 69-point win over Essendon in one of his standout games of the season.

Last month North Melbourne coach Alastair Clarkson was hit with a $20,000 fine for an "inappropriate" outburst towards St Kilda players Jimmy Webster and Dougal Howard.