Krylia Sovetov coach Igor Osinkin believes Arsen Zakharyan won't be ready for Chelsea in January.
The Dynamo Moscow winger is expected to sign for Chelsea next month.
But Osinkin told Sport-Express: "Zakharyan has more practice in the championship of Russia. It is not without reason Chelsea is interested in him.
"But, I think, for today he is not ready to immediately get a place in the starting lineup of Chelsea.
"He will need adaptation to foreign football. He is very promising. But he is not ready here and now to play there from the start."