Brazil forward Gabriel Barbosa believes tougher challenges lie ahead after Dunga's side opened their Copa America Centenario campaign with a goalless draw against Ecuador.
The 19-year-old forward came off the bench during the second half of the stalemate in Pasadena, shortly before Ecuador's Miler Bolanos had a goal controversially disallowed in the 66th minute.
Peru beat Haiti 1-0 in Group B's other fixture and Gabriel believes Brazil must sharpen up their end product in Neymar's absence when they take on the Central American nation in Orlando on Wednesday.
"I don't believe this has been our most complicated opponent," Gabriel told reporters.
"Every match is difficult, every national team has been strong for a while now. So, regardless of that, we must get on the pitch and try to play our game.
"I think we failed at the last pass today. It was a good game, very difficult and well-fought, where we created chances but failed to score. But I believe we had a good performance, overall."