The same source claims the Russian club officials are currently in talks with the player’s representatives, and the two parties are close to reaching an agreement.
Carvalho’s agents are requesting a contract worth €3.5 million per season, but Rubin Kazan hope they can negotiate a lower salary.
With his contract at Santiago Bernabeu expiring at the end of the season, the Portuguese footballer is free to negotiate a Bosman deal with interested clubs, but there is a chance he will move to Russia in the January transfer window.
Carvalho is likely to request a contract termination provided he can reach an agreement with Rubin Kazan, in which case he would be free to join the Russian giants in January.
The 34-year-old defender has done pretty well every time he was called upon this season, with his experience likely to prove a major asset for Kurban Berdyev’s side.