Chelsea striker Didier Drogba will miss his side's clash with Manchester United on Sunday after failing to recover from a head injury.
The 33-year-old was knocked unconscious three weeks ago after an aerial collision with Norwich City keeper John Ruddy.
Despite resuming training, Blues manager Andre Villas-Boas says that it is too soon for the Ivorian to feature.
"Didier had a medium intensity session yesterday (Thursday) and a high intensity session today (Friday) but it is a week too soon to go with him for Man United," said Villas-Boas.
Chelsea go into the match at Old Trafford in third place, two point behind league leaders United.
