THE INTRODUCTION of a national AFL reserves competition appears unlikely, with Gillon McLachlan playing down the prospect.

The League chief executive confirmed his team is looking at the second tier of football, but an "expensive" national reserves competition is not on the radar.

"I think it's challenging logistically and financially to have a national reserves competition and I think it would be to the detriment of the local competitions of the SANFL and the WAFL," McLachlan said in Adelaide on Thursday.

The AFL hasn't had a stand-alone reserves competitions since 1999.

Almost every Victorian team now has its own side in the VFL, or at a the very least an integrated program.

North Melbourne will field its own VFL team for the first time next season after ending its affiliation to Werribee, while St Kilda's grip on the Sandringham Zebras is highlighted by club great Aaron Hamill taking the reins as coach in 2018.

Port Adelaide and Adelaide have second-tier teams in the SANFL.

"People have a view about Port and Adelaide being in the SANFL but I think it loses something if they weren't here, that's my personal view," McLachlan said.

West Coast and Fremantle are affiliated with WAFL clubs East Perth and Peel Thunder respectively, while the four New South Wales and Queensland clubs field reserves sides in the NEAFL.

The League's resources have already been stretched to expedite the arrival of the new AFL Women's competition which will expand in 2019 and again in 2020.

The proposed experiment of the AFLX format also points to other priorities at League headquarters.