The midfielder replaced Paulinho at half-time in Brazil's Group A clash with Cameroon on Monday and sealed a 4-1 win with six minutes remaining.
Fernandinho could be handed a start in the host nation's last 16 clash with Chile on Saturday and the 29-year-old believes his decision to join Premier League champions City from Shakhtar Donetsk last June has been vindicated.
He told FIFA.com: "I've always dreamed of playing in the World Cup and wearing the Selecao jersey, but I knew how difficult that was, what with me playing in Ukraine for Shakhtar
"Last year, though, when I moved to England and began playing in a much bigger league with a much higher profile, I could see things coming together for me.
"I fought hard, chased my dream and got the call-up for the game with South Africa in March. Everything I did from June 2013 onwards was with the goal of making it here to the World Cup."
Brazil face South American rivals Chile at Estadio Mineirao in Belo Horizonte.
