Gabriel Jesus and Alex Telles have been ruled out of the rest of the World Cup after picking up injuries in Brazil's 1-0 defeat by Cameroon on Friday.
The pair both sustained right knee injuries and underwent MRI scans on Saturday morning.
In a statement, Brazil's football association said it was "impossible" for them to participate any further in the tournament in Qatar.
Favourites Brazil play South Korea in the last 16 on Monday (19:00 GMT).
It is yet to be decided if Arsenal's Jesus and Telles - on loan at Sevilla from Manchester United - will remain in Qatar or return to their respective clubs for treatment.