This is from I Am The Secret Footballer;
And this is where you will find an interesting breed of footballer –the player who regularly changes clubs. Financially, there is a fortune to be made in the Premier League just by moving clubs, and it works like this: as long as a player doesn’t officially ask to leave his current club, he is legally entitled to the remainder of the value of his contract (this is nullified if you hand in a transfer request).
If you sign a fixed length contract, it has to be fulfilled, unless both parties agree to nullify it.
A lot of the compensation a club asks for (transfer fee) is to cover the cost of paying up the player's remaining contract.
It's not as black and white as FIFA would have you believe.
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