Rangers made £550,000 from the transfer of starlet Billy Gilmour to Chelsea two years ago - but it has emerged the deal also cost the Ibrox side a £7800 fine.
Teenage ace Gilmour made his latest top team appearance for the Londoners in their Carabao Cup defeat to Manchester United on Wednesday evening as his star continues to rise south of the border.
The Scotland Under 21 star swapped his Ibrox dream for a crack at the Premier League in August 2017 with Rangers receiving just over half a million pounds in compensation.
But he has been caught up in the Blues' two-window transfer ban which was imposed in February for a number of rule breaches involving young players.
FIFA's findings released as part of Chelsea's appeal against the ban, show that the Premier League giants and Rangers entered into an illegal third party agreement in May 2017, two months before the transfer was completed.
That meant Rangers could not sell or loan Gilmour to any other club without the consent of Chelsea despite the youngster still being a Rangers player.
The agreement also stated that at any point the then 16-year-old could be released to train with the Stamford Bridge club and play in friendly games whenever they pleased.
FIFA's findings state: "The committee has no doubt that these clauses entitled CFC to influence on the policies of Rangers and Ajax, since it could prevent them from loaning the player to another club.
"In this respect, the committee considers that clubs, in order to be considered truly independent, shall be free to negotiate and loan their players with no need to obtain the authorization from another club.
"Likewise, the committee is of the firm opinion that clause 6.1 (d) of the Rangers agreement and 5.1 (d) of the Ajax agreement limited the independence of the respective clubs, since they had the obligation, upon request of CFC, to release the players in question so that they could attend take part to specific trainings and matches with CFC.
"Once again, the committee considers that these clauses entitled the appellant to influence both Rangers and Ajax in transfer related matters. Indeed, said clubs would be obliged to release the players upon request of CFC, regardless of whether it was in their sporting interest to keep them with their team."
Rangers were fined £7,800 for their part in the agreement. Ajax were hit with the same penalty for entering a similar arrangement with Chelsea over Juan Carlos Familia Castillo.
In total FIFA's appeals committee upheld a total of 150 alleged breaches involving 71 young players.
