The Liverpool duo played the entirety of the Group A encounter in Salvador that ended in a goalless stalemate.
Firmino did put the ball in the back of the net with 38 minutes played, but the goal was disallowed after the 27-year-old was adjudged to have committed a foul in the process.
Brazil, who beat Bolivia in their tournament opener, are next in action on Saturday when they face Peru in Sao Paulo.