Roberto Di Matteo admits the club may have to look at January replacements for Victor Moses and John Obi Mikel.
The pair will be away on duty for Nigeria at the African Cup of Nations in South Africa and Di Matteo says they will have to consider bringing some reinforcements in during the winter transfer market.
"We're looking at that, because we'll lose Victor and John Obi Mikel for that tournament," Di Matteo said.
"We'll look and see how we deal with it, but for the moment we're okay."
Nigeria take on the likes of Zambia, Burkina Faso and Ethiopia in Group C with their opening clash against Burkina Faso in Nelspruit on January 21.