Chelsea skipper John Terry is a doubt for Tuesday's Champions League clash with Paris Saint-Germain.
The experienced defender was forced off after 37 minutes of the 5-1 demolition of Newcastle on Saturday night, having been involved in an early collision with Aleksandar Mitrovic.
And manager Guus Hiddink is concerned that the last-16 clash with the French champions in Paris may come too soon for Terry.
"Tomorrow we will know," said Hiddink. "He has, hopefully, a small muscular problem, but tomorrow we will know how serious it is."
Asked if he expected to have Terry available for midweek, he added: "Midweek is already Tuesday and we have just two days to recover.
"I think teams need at least three days but we don't have it, so we will see what will be the outcome tomorrow."