The 33-year-old won four Premier League titles and the Champions League in his eight seasons at United between 2007 and 2015.
Speaking to Tribuna Expresso, Nani said: "No. I never felt in the shadow of Ronaldo, [Ryan] Giggs or Rooney.
"And there were no shadows at that time. We had a fantastic team.
"I played with Ronaldo lots of times as a starter. Our team had two or three playing styles and when it came to facing certain teams it was Nani and Ronaldo, while others were Ronaldo with Rooney.
"I was fortunate that when I came to Manchester, I played a lot of games in my first two years there and I was one of the most used players in the Champions League. So I have no reason to complain."