"I won't say how much the lad earns, but he has a contract until 2016 with CSKA and his primary objective is to play football, so money would not be a problem," agent Jean Bernard Beytrison told Radio CRC.
"I read that Napoli would like to sign a player with his characteristics, but I haven't yet spoken to any directors there.
"Doumbia really loves the way Napoli play and he would be perfect for Mazzarri's tactics. He already knows European football well, having played in Switzerland and Russia as well as Japan.
"I can say that Doumbia is crazy on the field, in the sense that he tries to score in every way possible or imaginable.
"In everyday life though he is very calm, doesn't go out late at night and prefers to stay home with friends."