A SPECIALLY-CONVENED AFL panel, not the Australian Sports Anti-Doping Authority, would hand down any penalties to Essendon over the possible use of banned supplements.

While ASADA is investigating Essendon's sport science practices last season, as well as possible use of banned substances by one other AFL player, any sanctions would come from a League-appointed panel.

The AFL is yet to say who would sit on such a panel, but has confirmed it would consist of two senior lawyers and a medical professional with previous experience in anti-doping hearings.  

If the panel is required, it would hear cases against individuals, not one case against the club.

Former ASADA chief executive Richard Ings said the anti-doping body could recommend a penalty, but the AFL panel would determine any sanctions.

But Ings dashed any hope players may have of serving a ban in the off-season, saying the AFL tribunal would be compelled to follow World Anti-Doping Agency guidelines.  

"The suspension has to be a period from playing footy, not a period of having a holiday," he said.  

"The idea is that you can't play for six months, and the tribunal can set the start date at a point where there is a penalty in terms of how much on-field play they could do."

AFL chief executive Andrew Demetriou admitted on Wednesday he didn't expect a quick resolution of the ASADA inquiry.

"No, I don't think you're going to see a result for months," he told reporters.

"ASADA are going to be very thorough and very diligent. These things don't happen quickly; there's lots of people that have to be interviewed, there's lots of things that have to be checked.

"Our expectation will be that this will go on for months."

Ings said the lack of positive test results meant a lengthy investigation was the only way to go, with interviews, medical records and other evidence all key parts of the inquiry.

"They've got to go through all these steps, because they need multiple corroborating pieces of evidence to mount what's called a non-analytical case against a player.

"Because you haven't got a positive, you need more evidence to make it happen."

Matt Thompson is a reporter for AFL Media. Follow him on twitter @MattThompsonAFL