AFL chief Gillon McLachlan and former chairman Mike Fitzpatrick have moved a step closer to having to appear in the witness box to explain their actions in the Essendon supplements saga.

Supreme Court judge John Dixon ruled in favour of Melbourne lawyer Jackson Taylor on two key issues on Wednesday. Taylor has fought against the AFL for years, alleging McLachlan and Fitzpatrick engaged in misleading or deceptive conduct through the scandal which rocked the sport when exposed in February, 2013.

AFL chief executive Gillon McLachlan. Credit:Joe Armao

Dixon ruled in favour of Taylor over whether McLachlan and Fitzpatrick had made comments that were "trade or commerce" under Australian consumer laws, and whether part of the case, as the AFL had argued, should be held at a mini-trial to cut expenses – the AFL has estimated a full trial could cost $700,000 – in a bid to limit the number of witnesses and discovery of documents. Taylor did not want a preliminary hearing.

Dixon's ruling means that there is still the possibility of McLachlan and Fitzpatrick being forced to give evidence at trial. No senior AFL executive has faced questioning in court throughout the saga.