Lyon striker Bertrand Traore is at the centre of Chelsea's two window transfer ban, it has been revealed.

The Burkina Faso winger moved to Lyon in summer 2017 for £8.8million.

And FIFA's investigation into Chelsea's transfer business — which has resulted in a ban for the summer and winter windows, pending Chelsea's appeal — was caused by the circumstances surrounding Traore's move to Stamford Bridge.

Their regulations state there are only three situations in which a player under the age of 18 can move internationally.

The first is if a player's parents move for non-footballing reasons. Another is if they are within the EU, and the last involves proximity to a border.

None of those would have applied to Traore.

While he signed for Chelsea at 18 in January 2014, the Daily Mail claims there are questions over Traore's status leading up to the signing.

However, Tribalfootball.com can reveal Traore's contract was investigated by FIFA at the time. And Chelsea are likely to use their original defence as part of their new appeal.

Chelsea argued that Traore "was party to an option agreement which enabled the club to acquire his registration in January 2014.

"The option agreement was registered with, and approved by, both The FA and the Premier League."