FORMER Essendon biochemist Stephen Dank has claimed Dons coach James Hird was a "keen supporter" of the club's controversial supplements program in 2012. 

On Monday night, Dank refused to comment on the details of the now infamous program being investigated by the Australian Sports Anti-Doping Authority, but reinforced Hird as a key component. 

"He was a keen supporter of the program," Dank told Channel Nine’s Footy Classified.

"I think we did a very good job with that program."

Dank also weighed in on a News Limited report that an undertaking had taken place between the AFL and ASADA in February to "explore all avenues" for the embattled club.

"Let’s be clear - they’d better be very, very careful if these assurances were given," he said.

"Let’s just say there are a number of issues because of that, and I think both ASADA, the AFL and the Essendon Football Club need to be very careful if that’s true."

On Monday, ASADA insisted there was no deal in place for Essendon players to be offered a "zero sanction" over the club's controversial supplements program.

But the national sports doping regulator has confirmed it did establish a process with the AFL shortly after the Australian Crime Commission's bombshell report into drugs and organised crime in Australian sport was released in February.

"Given the number of players involved, it was important to have an orderly process to encourage players to come forward," an ASADA spokesperson told AFL.com.au.

"ASADA has not offered a zero sanction to any athlete or support person."

Dank said he would explore the finer details of the supplements program at a later date. 

"To be reasonably honest I can’t comment on anything like that because I’ve said to you everything will end up in court. I’m leaving all documents and all evidence for the court hearings," he said.