Ecuador almost equalised six minutes later but Enner Valencia's right foot shot hit the base of the post after beating goalkeeper Jefferson.
The West Ham United striker also had a looping header cleared off the line by Filipe Luis 16 minutes into the second half as Ecuador enjoyed their best spell of the game.
Brazil's best chance of the second half fell to Neymar in the 47th minute but the Barcelona striker missed an open goal from four yards out with the keeper on the ground.
Ecuador fielded a young team but they were quick and fearless and frequently stretched a Brazilian back four that had never played together at international level.
The quartet of Danilo, Marquinhos, Miranda and Filipe Luis defended well, however, and a midfield featuring the Chelsea trio of Oscar, Willian and Ramires hassled and harried from the start.
Brazil had the best of the first half but they made several changes after the break, giving debuts to Cruzeiro striker Ricardo Goulart and Corinthians defender Gil and allowing Ecuador to get back into the game.
Neither side dominated a fairly even match for long periods, however.
The win was the second in a row for Dunga since he returned to coach the Brazil side after their disastrous World Cup. On Friday, they beat Colombia 1-0 in Miami with a late goal from Neymar.
Brazil's next match will be against Argentina in Beijing on Oct. 11. Dunga's first competitive fixtures will come in next year's Copa America in Chile.
(Reporting by Andrew Downie in Sao Paulo, editing by Nick Mulvenney)
Share
