(CNN) -- He revolutionized football once before by transforming its transfer system -- now Belgian lawyer Jean-Louis Dupont is gunning to change the face of the game for a second time. In his sights is UEFA's shiny new regulatory regime: Financial Fair Play (FFP), which has become the scourge of Europe's richest football clubs, notably English champion Manchester City and top French side Paris Saint-Germain, which were both heavily sanctioned by Europe's governing body Friday. FFP is designed to prevent clubs spending beyond their means and posting unsustainable yearly losses, but Dupont believes the sanctions are "completely illegal" because they restrict competition -- a key principle of European Union law.
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Lawyer brands UEFA's Financial Fair Play sanctions "illegal"
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Belgian Jean-Louis Dupont is the man who transformed system with "Bosman ruling"
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Dupont says FFP contravenes European Union competition law
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Belgian lawyer calls on fans to lodge complaints with Brussels
Dupont believes FFP raises further competition concerns by entrenching the status quo, by not allowing clubs like @placeholder and PSG to challenge the established football order in future.