The Sevilla man proved the difference as A Selecao claimed the honours in South Africa.
Fabiano was on fire in front of the goal as his brace helped Brazil pull off a comeback against the USA to win the final 3-2.
Dunga's choice to use Fabiano had been far from popular among some of the supporters of the Selecao.
The coach is now confident that Fabiano's displays in the Confederations Cup will silence the Sevilla man's critics.
"I have heard some people say that Luis Fabiano scores goals but is not good for the national team," Dunga told the press after the game.
"In the way I see football, a good striker is that who scores goals. And he does that.
"Once, we were in a training in which the players could touch the ball just two times and some players would send the ball wide when in front of the goal.
"But not him. He would go there and score, because he is hungry for goals. That's why I decided to put him on the team."
Luís Mira, Goal.com
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