"Under an agreement reached by the Brazilian national team's technical commission, Alexandre Gallo departs as coach of the Under-20 and Olympic teams after 27 months," the CBF statement said.
"Mario Rogerio Reis Micalle will take over at the Under-20 team and the Olympic side will be led by coach Dunga until the 2016 Olympics."
Dunga has revitalised the national team after taking over in the wake of their dismal World cup last year.
The Games will be held in Rio de Janeiro next year and the Olympic title is the only major international competition that Brazil have never won.
Image: Carlos Dunga is introduced as the new coach of the Brazilian national football team during a press conference at the Brazilian Football Confederation - CBF headquarters in Rio de Janeiro
Photo: Buda Mendes/Getty Images
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