Mandic came in for heavy criticism from Leeds for his handling of the transfer saga, and Fifa are now set to launch a probe into the deal which saw the agent's company pocket a reported £2 million of the £5 million fee.
However, Mandic insists he was merely acting within the rules set by the clubs themselves, and was doing nothing more than looking out for the best interests of his client.
"I work within the framework the game gives me," he hit back.
"It is an environment the clubs have created and are responsible for - because they're a bunch of sharks that will destroy each other at the drop of a hat.
"The clubs openly have preferred agents that they like dealing with. The question is, where does that money go?
"I'm not denying this is a murky world.
"The thing is, with Harry Kewell and myself, we've done it our way and on our terms.
"If we've offended people, so be it."
Mandic went on to turn the tables on Kewell's former employers Leeds, claiming the Yorkshire outfit were far from blameless in the player's protracted departure from the club.
"Football has regulations but they are meant to work where a player is consulted in all aspects of the process of being sold. It doesn't happen.
"In football we like to play silly little emotional games about loyalty and values that Leeds loved to talk about.
"These guys tried to sell Harry to the highest bidder last December - behind his back, behind my back and behind the back of MAX Sport who they knew were his legal representatives.
"If that's loyalty, I think they got too much money."
