It has been reported that Chelsea will have to wait before finding out exactly what is wrong with Oscar.
The Brazilian international playmaker was clattered by Arsenal goalkeeper David Ospina in the first half of their 0-0 draw at the Emirates Stadium on Sunday.
Oscar was taken to hospital after being replaced by Didier Drogba at half-time but Mourinho was unaware of the extent of the injury straight after the match.
“He went to hospital at half-time. I don’t know (if it is concussion), we are waiting,” he said.