The Brazil international, now playing for Wolfsburg, dismisses suggestions that he left the reigning Bundesliga champions due to the former Barcelona coach's influence
The holding midfielder left the Allianz Arena for Dieter Hecking's side earlier in August, snubbing a move to Arsenal, and has stressed that the Spaniard was not the reason for his departure.
"It's never easy to say farewell. I met a lot of friends at Bayern and a lot of people will always have a place in my heart, including Pep Guardiola," the Brazil international told Sport Bild.
"He did not tell me that I did not have a chance at Bayern. He also shook my hand and said me farewell on the Sunday of my goodbye.
"I could have stayed at Bayern and fought for my place. I have no doubt that I would have achieved something.
"I felt that something had to change. That feeling got even stronger after a first meeting with Guardiola. I then spoke with the people who are important to me and made my decision."
Gustavo, 26, made his official Wolfsburg debut on Saturday, helping them to a 4-0 win over Schalke.