David Luiz could miss Chelsea's Champions League quarter-final return leg against Benfica on Wednesday night.
The 24-year-old limped off with an ankle injury in the latter stages of the first half during the Blues' 4-2 win at Aston Villa yesterday.
Speaking after the game, interim manager Roberto Di Matteo revealed that the Chelsea medical staff will review the problem early next week.
"We'll have to wait for 48 hours to asses David Luiz. He felt his ankle ligaments and came off," Di Matteo explained.
Luiz arrived at Chelsea from Benfica in January 2011 for a fee of around £24m.