The two-time world champion is confident Dunga can lead his men to Russia 2018 but warned they face the most competitive process in history.
Former Brazil star Ronaldo says his country must navigate the most competitive qualification process in World Cup history to book its place at Russia 2018.
The Selecao return to action in October when they open South America’s marathon qualification process against Copa America winner Chile in Santiago before then hosting Venzuela.
Two-time World Cup winner Ronaldo has warned Dunga’s charges that they face the Selecao’s greatest-ever challenge in a 10-team group without a single minnow.