Chelsea have been banned by FIFA from registering new players for the next two transfer windows after being found guilty of inducing a player to break his contract with another club.
"Chelsea are banned from registering any new players, either nationally or internationally, for the two next entire and consecutive registration periods," FIFA said in a statement on Thursday.
The punishment was handed out by world soccer's governing body following a contractual dispute involving the transfer of reserve team player Gael Kakuta from Racing Lens in 2007.
LENS COMPLAINT
Following a complaint from Lens, FIFA's dispute resolution chamber ruled Kakuta, now 18, had breached his contract with the French club and that Chelsea had induced him to do so.
The player was ordered to pay 780,000 euros ($1.11 million) compensation, which FIFA said Chelsea were "jointly liable" for, and he was given a four-month ban from competitive matches.
Chelsea were also ordered to pay "training compensation" of 130,000 euros to Lens.
The Premier League club could appeal against the decision to the Court of Arbitration for Sport (CAS), the sporting world's top tribunal.
CAS usually takes around four months to decide cases and generally suspends punishments until the hearing takes place.
Hampered by injury, Frenchman Kakuta made only five youth team appearances and two in the reserves last season.
He began last season with hamstring problems before being sidelined in February after suffering a double fracture of the ankle in a friendly.
Kakuta's first season was more successful as he finished as the youth team's top goal-scorer.
In May, Swiss club Sion were banned by FIFA from registering new players for one transfer period following their controversial signing of Egypt goalkeeper Essam Al Hadari from Al Ahli last year.
The ban was put on hold by CAS in July after Sion appealed.
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