The Age has reported that Clark fell out with Duncan following a ‘sledging incident’ at a VFL game.
Duncan is said to have confronted Clark after he was told the forward made derogatory remarks about his partner, to her brother, Teia Miles, who is a Hawthorn listed player.
The alleged incident took place three weeks ago at Simonds Stadium against Box Hill and Clark is understood to have directed the insult to Miles on several occasions during the match.
The Age reports that Clark has told Geelong that he was provoked by Miles before the incident occurred.
Geelong officials were reportedly unaware of the incident until Monday when they were contacted by Fairfax.
Cats’ officials then confronted Clark about the matter, with the club satisfied that the two players had dealt with the issue and the matter is now considered closed.