The AFL has started landmark mediation proceedings with a transgender footballer who says her vilification case has been mismanaged for six weeks because it was ''new'' and ''too hard''.

Kirsti Miller, who is still being asked by the AFL not to discuss her grievance publicly, made a formal written complaint to Broken Hill Football League's president the day she was verbally abused by opponents and spectators during a match, with one player saying she should ''show me your cock''.

Vilified: Kirsti Miller in Broken Hill. Credit:Darrin Manuel

But after initially having the support of her teammates and club, Miller has been frozen out of Broken Hill Souths, apparently after she used social media to decry the abuse - a response that was picked up by local media.

AFL NSW-ACT, which has suggested the case has been poorly managed locally, co-ordinated a mediation session on Wednesday night for the 48-year-old former international modern pentathlon champion who says she has identified legally as female for seven years.