THE AFL has refused to reveal if it will investigate serious allegations of match-fixing, illegal gambling and drug use levelled at the Brisbane Lions.

Jason McGrath, the cousin of Lions premiership player Ash McGrath, has made a series of threats to expose behaviour at the club between 2002 and 2009, as the fallout continues from Australian sport's doping storm.

Jason McGrath, a confessed drug dealer, was seen in the Lions' dressingrooms and at functions at times during that period.

The newspaper made contact with Jason McGrath after he made a series of Facebook posts claiming he was ready to expose dodgy AFL practices: "If you don't think the drugs and match-fixing is real, I bet on the AFL and was involved in a game being fixed."

He told the newspaper he had been a drug supplier between 2002 and 2009 and named six Lions players from that period who were heavy users of speed, ecstasy and marijuana.

He said members of the Lions' coaching staff knew some players were regular drug users.

Lions chief executive Malcolm Holmes refused to confirm if the club would investigate the claims or pass the allegations on to the AFL.

"The Brisbane Lions do not comment on unsubstantiated allegations, rumour or innuendo," Holmes said.

The AFL has also refused to say whether it will look into Jason McGrath's claims.

The Courier-Mail can confirm the Lions administration at the time had heard suggestions about drug use by two of the players in question.

Jason McGrath claims to have been involved in fixing a match involving the Lions in 2003, another instance of spot fixing, and to have regularly received inside team information from Lions players just before games for the purposes of betting.

Jason McGrath also told of an occasion where he had delivered an ounce of speed to a Mad Monday celebration at the Broadway Hotel, another where a player was hospitalised after a binge on speed, and multiple times where players had smoked pot in his home.

He also said he had supplied cocaine to players on occasion.

Four players named by Jason McGrath are still playing in the AFL.

He also claimed he would provide to the newspaper betting slips and phone records to substantiate his claims about match-fixing, but he has since gone to ground and refused to return phone calls.

He claims to have received threats from a current player after making his Facebook posts.