Asked about Ramos' apology to his teammates for a damaging interview last week, Heinze said: "The truth is we must keep it in the dressing room, which is the holiest place for soccer players.
"Sergio has said what he thinks and that's it. He spoke with the coach and it stays there. What was shared is not being made public."
Heinze added: "Ramos was right in some things, but not all. He is the best when he can join the attack and if he can play well he is the best in the world."