The Cameroon striker said: "He isn't playing and every player has the chance to take charge of things only on the pitch. Football and form is like the stock market. It goes high and low.
"But behind the scenes many things can happen. We know how much a player is worth and what he can contribute. People must remember what Ronaldinho has done for football, especially when you see the stories about his private life."
Asked about coach Frank Rijkaard's future at Barca, Eto'o added: "There's no reason to change anything. The difference between an average player and a champion is here (tapping his head)."