The defender has just won a recall to the Brazil squad.
"Am I a gamble for Roma? No, I have nothing to prove to anyone. I just have to show what I can do on the field," said the 32-year-old.
"I chose Roma because they wanted me with their heart, which is important for a player. I am ready and at their disposal, so hope to repay their faith in me.
"Coach Rudi Garcia put a lot of faith in me. He called when I first arrived and said he wanted me in his team. He did well in France, so I hope he can follow that on here.
"We have an important squad here. I have to do my job and the club must do well with the players at its disposal.
"Francesco Totti is a great champion and beyond description. I'm happy to be playing alongside him."
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