Fallen AFL star Ben Cousins never agreed to an exhibition fight as promoted by world middleweight champion Anthony Mundine, according to his manager Ricky Nixon.

Nixon said Cousins told him yesterday that he would not be fighting and had never agreed to the bout mooted for the undercard of Mundine’s WBA middleweight defence next week in Sydney.

Nixon said Cousins' decision not to fight had nothing to do with reports that the footballer would have to undergo drug testing before being allowed to fight under NSW regulations.

Nixon suggested that Team Mundine did not have Cousins' best interests at heart and was only seeking to profit from the former West Coast Eagle's predicament.

"The next time Mundine wants to promote his fight, let him hire a PR company," Nixon said.

"If they try to persuade Ben to fight and he goes along with it, I will personally go to Sydney and physically stop him from getting in the ring.

"This is distasteful to all Australians, the sight of Mundine using Ben's tragic circumstances to make money."

Cousins received a 12-month playing ban from the AFL after being found guilty of bringing the game into disrepute. This followed a string of drug-fuelled incidents over more than five years.

Cousins is reportedly still struggling with a dependence on illicit and prescription drugs and clinical depression.

Cousins made his first public statement on his drug rehabilitation at a Team Mundine press conference this month when it was announced the premiership player would fight in the exhibition bout.

It's understood Cousins simply went along with the announcement of the bout at the press conference.