Essendon and one other AFL club named Essendon are set to start the AFL season under a cloud of suspicion, with an investigation into the potential use of performance-enhancing drugs by multiple Bombers players likely to take months to complete. AFL deputy chief executive Gillon McLachlan confirmed on Sunday Essendon was the one AFL club being investigated for possible multiple breaches of the World Anti-Doping Authority (WADA) code following the Australian Crime Commission (ACC) report. "I think it's reasonable to say, given that the Essendon football club has come forward to the AFL and to ASADA, and proactively advised us of concerns they have, it's reasonable to talk to that," said McLachlan. The AFL is aware of potential multiple breaches at that club. A single player from another club was also being investigated, although McLachlan refused to reveal his identity. "The AFL is aware of one case involving the possibility of WADA prohibited performance-enhancing drug use by one player at one club," said McLachlan. The AFL is aware that a second case involves the possibility of WADA prohibited performance-enhancing drug use by multiple players at one club. In this case it's possible that players were administered the WADA prohibited substances without their knowledge or consent. The Bombers play the opening match of the home and away season against Adelaide at AAMI Stadium on March 22. It was unlikely the investigations into alleged drug abuse at Essendon and by the other player would be completed by then. "It's not going to be as quick as everyone would like," said McLachlan. The reality is that the investigators, which is ultimately ASADA in partnership with the AFL, have to get the right answers and that will take as long as it takes. It's more likely to be months rather than weeks. That means that if Essendon or any of their players are found guilty of doping breaches, any penalties would be imposed after the season had begun. Essendon went to the AFL with concerns over supplement use before the ACC handed down their report on Thursday. But it was not until Sunday, when federal Justice Minister Jason Clare said any AFL or NRL clubs under suspicion could out themselves, that the AFL confirmed Essendon were the club named in the ACC report for alleged multiple breaches. "We've given the names of the clubs to both the NRL and the AFL," said Clare. And the NRL and the AFL have asked for permission to tell the clubs that are affected by the investigation. McLachlan said the AFL was also aware of other cases involving illicit, but not performance-enhancing, drug use. But the league had not been warned of any specific instances of suspected match fixing in AFL competition.