Didier Drogba has been diagnosed as suffering from malaria, Chelsea coach Carlo Ancelotti has confirmed.
The Ivory Coast striker was thought to have been suffering from a virus in recent weeks but blood tests revealed it was the tropical disease.
Drogba was left out of the starting line-up for the 2-0 defeat at Liverpool but came on as a second-half substitute after complaining of a fever on the eve of the game.
"We found out last night when blood tests showed he had malaria," said Ancelotti. "I don't know where he got it from."
Despite suffering from the disease, Drogba will start against Fulham at Stamford Bridge on Wednesday.