Hulk's 10th minute strike was enough to seal a 1-0 win over Costa Rica for an off-color Brazil.
Brazil began preparations for its World Cup qualifying campaign with a 1-0 friendly win over Costa Rica in New Jersey on Saturday.
In its first game since a disappointing Copa America exit at the hands of Paraguay, Dunga's experimental side raced out of the blocks and took the lead after 10 minutes.
A loose ball inside the area was pounced upon by an onrushing Hulk, who shook off his man before applying a composed finish.
Despite Costa Rica failing to register a single effort on target, Brazil could not build on the lead, with Marcelo and Douglas Costa both spurning good opportunities after the break.