And all of a sudden, the run is over. Dunga and Brazil's stretch of 11 successive wins was brought to an abrupt halt on Wednesday night by Colombia, whose 1-0 win in Santiago, Chile, left Group C in this Copa America wide open.
With Peru and Venezuela playing on Thursday evening, there is the possibility of all four sides sitting on three points after two games, should the former manage to win.
From the Selecao's point of view, it is a wasted opportunity to take charge of a group following Colombia's shock defeat to Venezuela last weekend.
Furthermore, the Brazilians will now have to make sure of qualification without their talisman, Neymar.
A rash moment at the end of the game saw the Brazilian No. 10 and Colombian Carlos Bacca both dismissed, leaving the eight-time Copa America champions with a mountain to climb.
On the evidence of the two competitive games Dunga has taken charge of so far, rousing this side without the influence of their greatest player will be a tall order indeed—especially against a Venezuelan outfit that is likely to be brimming with confidence following one shock victory already.
Dunga had made two changes to the line-up before kick-off. In came Thiago Silva for David Luiz in the centre of defence, while Roberto Firmino was handed the task of leading the line in place of Diego Tardelli.
Certainly, his decision to replace the man leading his line may weigh heavily on the boss in the coming days. The Hoffenheim forward missed a golden chance to secure at least a share of the points, blazing a chance high over the bar with the goal at his mercy.
Tardelli, watching from the bench, can certainly have considered himself unlucky to not have been given another chance in the starting line-up.
Now the coach has a huge decision to make ahead of the final, decisive group encounter this Sunday.
But where Brazil went missing was in the midfield, with the trio of Fernandinho, Elias and Fred failing to dominate or even effectively break up their opponents' passing game.
Perhaps now the importance of Luiz Gustavo to the balance of this side will be appreciated. Without his calming and dependable presence in front of the back four, Brazil lose a stabilising effect in the midfield—something Fernandinho, deputising for Gustavo, has so far been unable to replicate.
The encouraging news for Dunga was that the introduction of Philippe Coutinho gave this side a much-needed injection of life and creativity.
And with Neymar now set to miss Sunday's match with Venezuela, the onus could well be on the Liverpool playmaker to be the telling difference, alongside Tardelli, Firmino or both. Firmino's confidence cannot be high following a disappointing start to the tournament.
If anything, the absence of Neymar this weekend will be the perfect opportunity for the two to show their worth to this side.
With Willian and Coutinho as providers, whoever plays further forward simply must show they have the capability and temperament to be the protagonist for this side in the absence of their shining light.
What not only this result but also this performance showed is that this remains very much a Brazil side in transition. Dunga's team are a work in progress, and all the solutions do not lie ready-made in the palm of his hand.
As soon as the final whistle blew, the same complaints that were made at the World Cup were made by television pundits—most notably that this team is over-reliant on Neymar.
But with a freakish talent such as the 23-year-old among their ranks, it is only natural that he should be the beacon others look to in the same way all top-class players lead from the front, no matter who is around them.
Now, of course, there is a job to be done without him, but that is not to say all hope is lost. This Brazil squad still contains talented and disciplined players capable of grinding out a result, as the last week or so has proven.
No, the team did not play well at the Estadio Monumental, but it was the second match of a potential five-game tournament. To peak midway through the group stage would be of little long-term benefit.
Brazil go into their final group game against Venezuela with their fate still in their hands. Dunga has four days to find the solution to the biggest dilemma of his brief reign so far. But with the tools at his disposal, it is a task this team can still overcome.