Chelsea boss Rafa Benitez is seeking a boost from his Nigerian pair John Obi Mikel and Victor Moses.
The duo are available again after winning the African Cup of Nations.
"I think they will come back with more confidence, more belief and it has to be good for the team," Benitez said.
"It's important to have happy and confident players around, so it's good for the team that they won and they've brought that confidence and belief back with them.
"Both of them progressed as individuals through the tournament.
"Obi has more experience and you could expect good performances from him, but Victor was coming through and I could see he has been growing and improving.
"I am really pleased for both of them, and to be so influential is a great achievement for Victor."