The Brazilian midfielder had been on the verge of a January transfer to Gremio, but stayed on and saw Zdenek Zeman sacked two weeks ago.
"Football changes quickly. I always had my mind on Roma, but when you don't play then the desire does grow to seek another team where you'd be of more use...
"As I said, football changes quickly. Now Andreazzoli gives me more opportunities to play and I am happy, albeit aware I must always push to do better.
"Andreazzoli has changed the shape of the side, the way we play, but above all I think he changes our mentality. He asks us to be gritty and determined on the field, to always play with our heads and the right preparation.
"We had the right mentality against Juve, as we were all out there together with our hearts."