Dunga has said that his Brazil side remain haunted by their 7-1 mauling at the hands of Germany in last summer's World Cup on home soil.
The Selecao - then under Luiz Felipe Scolari - were obliterated at the semi-final stage 12 months ago in a defeat that sent shockwaves around the world.
Brazil's status took another hit last month when Dunga's men exited the Copa America after losing on penalties to Paraguay at the quarter-final stage in Chile.
However, the 51-year-old says that his troops still bear the mental scars of what happened to them in Belo Horizonte, with yesterday marking the first anniversary of the mauling.
"[July 8] is a date that will leave a mark, just like 1950, but also just like the five times that Brazil was world champion," he told Globo Esporte.
"We all have to improve. We need the humility to know that we have to work to recover that dominance of world football, but we also have to admit that it's not that easy.
"We have to see the positive side, though. We can't always win. We have to try to go forward in every way we can."
Dunga had previously won all nine of his games as coach - which is his second spell - before the Copa kicked off.
