Mendy, who joined Chelsea for a reported 22 million pounds ($28.47 million) from French club Stade Rennes in September, has returned to London and will undergo further tests.
Browsing: Stade Rennes
Financial details of the transfer were not disclosed but British media reported Chelsea paid around 22 million pounds ($28.01 million) for the 28-year-old who had three years left on his Rennes contract.
Paris St Germain forward, Neymar, has been handed a three-match ban and an additional two-match suspended ban for an altercation with a spectator following their French Cup final loss to Stade Rennes in April.
The Stade Rennes forward, on loan from English side Sunderland, is regarded as key to Tunisia’s hopes of making an impact in Russia.