Chelsea could reportedly be hit with a transfer ban should they be found guilty of breaching FIFA rules in relation to youngster Bertrand Traore.
The Premier League outfit have been accused of allowing Traore to play for their Under-18s side when aged 16, according to PA Sport.
The club have claimed that an option agreement was in place, giving the Burkina Faso international the green light to play in friendly games.
A FIFA spokesperson told PA: "We are not in a position to comment on any investigations that are ongoing so as not to compromise the process, nor do we provide any comments as to whether or not any investigations are underway."
Spanish giants Real Madrid and Atletico Madrid were punished for similar FIFA breaches - both clubs were banned from registering players in the next two transfer windows.
Both La Liga outfits intend to appeal the sanctions.
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