Illegal transfer dealings are rife within English football, according to a high-profile agent.
The agent, who spoke on condition of anonymity, told BBC Sport that both clubs and agents routinely break both Fifa and Football Association rules - and get away scot-free.
The agent claims that:
- players are frequently tapped up illegally by other clubs
unlicensed agents operate throughout the game
- certain agents illegally attempt to steal other agents' players.
And Graham Bean, former head of the FA's compliance unit, admitted the problems are almost impossible for the FA to deal with.
"Every time you think you've tied the loose ends up, you always find another loophole," he told BBC Sport.
Under Fifa rules, it is illegal for a club or agent to approach another club's player unless the two clubs have already agreed to a transfer and price.
But the agent claims existing regulations are regularly flouted by many within the game.
"The reality is that players have often already been tapped up before a transfer bid," he said.
"That means the buying club already have a pretty good idea of whether the player will go or not before they make their offer. That goes on at all levels - all throughout the Nationwide divisions as well.
"As licensed agents, we are not supposed to enter into any discussions with or on behalf of players contracted to us unless we are specifically authorised to do it by the club that has him at the moment.
"But it goes on all the time. It's been going on since time began."
To operate as an agent you must be licensed by Fifa, passing an exam set by the FA and taking out professional indemnity insurance to ensure good practice.
"Lots of the people involved are not licensed. There are lots of ways you can be active and not get found out," says the agent.
"The FA has a scheme whereby, if you look after a player, you have to have them under contract and send that to the FA. The FA then has a register of who looks after whom.
"But what happens is that players won't sign a formal commitment to an agent. They will say to agents, well, I'll sign with the guy who can get me a move.
"So you can have a number of different agents touting the same player around to try to get a bite. Then they will go back to the player and say, right, I've got you a deal with Club X, now you've got to sign with me. That's his way into the player."
The FA has defended its record in attacking corruption in the game, telling BBC Sport that much of its work was covert and so unlikely to come to the public's attention.
But Bean believes the FA is fighting a losing battle.
"Irrespective of how you want to window-dress it, you cannot get away from the fact that the world of agents is a very murky one," he said.
"That will always be the case, even if the authorities put in watertight restrictions on agents' conduct. Football is a cash business, and money ebbs and flows. You will never ever take away that.
"You have agents manipulating moves. And when it comes to sitting down and discussing personal terms, the agent might stop the move from going ahead, even if the player is happy with it, because the agent won't be happy with it.
"Agents have a stranglehold on the game that has taken all common sense out of it."
Air of suspicion
Bean is also concerned about the amount of money certain agents make from transfer deals in which - on the surface at least - they have played no part.
An agent may pass on a significant cut of his fee to another agent who has helped him make a particular deal - but the size and destination of payments are not always made public.
"These secondary payments further down the line have an air of suspicion around them," said Bean.
"Someone further down the line will have better contacts at the buying or selling club than the main agent doing the deal.
"So for his part in the deal he has to receive a payment, which is usually arranged between him and the agent - like a businessman sub-contracting work out in any other industry.
"And while there is nothing necessarily wrong with that, I just think in the football industry - when it has to be accountable to the public - that will be viewed with an air of suspicion.
"They have to look at plugging that gap."
The agent also told BBC Sport that players are often approached illegally by other agents, even if they are registered with an agent at the FA.
"They will phone the player, the player's mother and girlfriend and try to seduce them with talk of how they can make them more money. 'You shouldn't be signing for them, I can get you a better move,'" he said.
"Agents can always get access to your player, even if you have them under contract. Someone will know one of his team-mates, who will pass on his mobile number, and then they're in. It's murderously difficult for the player."
In response to the claims by the agent and Bean, an FA spokesman said, "A significant amount of work completed by the compliance unit is done so in a covert manner.
"Therefore the comments you have supplied to us from an unnamed top agent are likely to have been provided without the full knowledge of the extensive work which is ongoing in this area."
More on transfer corruption in football on the BBC Sport website:
On Friday: What can be done to clean up football?
On Monday: How to become a football agent.