The League Managers' Association has demanded "hard evidence" from the BBC's Panorama programme's investigation into illegal payments.
The LMA said: "As the organisation which represents managers we were very disappointed with the programme.
"There was a complete lack of substance and evidence, and if the BBC has any hard evidence it should give it to the Football Association."
HM Renevue and Customs has also indicated it will look into the claims.
A spokesman for the Revenue said: ""The same tax rules apply to sports clubs as to any other form of organisation and our compliance approach remains the same."
In a statement, the LMA added: "Our members are fully aware of their responsibilities and of the need to act professionally and with the utmost integrity at all times.
"There has been considerable debate about the transparency of the football transfer system and the role of agents both in this country and abroad.
"The LMA supports fully any thorough investigation on these issues and if there is any evidence of financial misconduct within football then let it be brought out into the open and the parties dealt with accordingly."
The ones in the programme were very low down on the food chain, if there's been something wrong let's put the handcuffs on them
Meanwhile, leading football agent Jon Smith claimed current FA regulations are toothless and ignored.
He said: "The FA's regulations don't work, are not enforced and nobody gives a damn about them.
"Until they get real and proper departments to deal with this there will always be allegations."
Smith says by introducing rule changes the FA can smooth the relationship between clubs and players' agents.
He added :"The FA made a complaint to us about a recent transfer being against Fifa regulations - a very small matter in the paperwork - but why bother when there are other fundamental things wrong with the regulations?"
Smith also claimed Panorama's investigations fell short of producing damning evidence.
He said: "I think they got near to the edge of the cliff but didn't fall off.
"There was allegation and innunendo but there wasn't actually any meat on the bone.
"At the end of the day, there was around £300m of Premiership transfer deals done last year, the big boys accounting for around 70% of that.
"The ones in the programme were very low down on the food chain and if there's been something wrong let's put the handcuffs on them."