The 19-year-old forward showed flashes of his exciting talent when he scored twice for Brazil against Ecuador on Friday evening.
“I've watched some games while he was playing with Palmeiras and I really like him," said Fernandinho to the club's website.
“He did well during the Olympics and scored twice on his full debut against Ecuador so he's doing really well and is a great talent.
“He has helped take Palmeiras to the top of the league and City have done a great job by bringing him to the Club.
“Of course, he is very young and needs to improve and grow but in all honesty I can't wait for him to arrive and start playing for us because I think he will do really well for us."