Midfielder Michael Essien has returned to Chelsea from Real Madrid for treatment on a mystery injury.
The 29-year-old's season-long loan at the Bernabeu has been temporarily put on hold while the Blues medical staff assess his condition.
Earlier this week Real assistant boss Aitor Karanka claimed that Essien, who has not featured for the Spanish champions since November 11, had suffered an allergic reaction to medication.
Essien trained at Chelsea's Cobham headquarters today.
He has made six La Liga appearances for Real this season, scoring one goal.