Fluminense cruise to the top
The veteran striker opened the scoring in the 21st minute and Emerson made it 2-0 nine minutes after the break.
Washington grabbed his second in the 69th minute to end the match as a contest, though Bruno Mineiro did pull one back six minutes from time.
Third-placed Ceara lost ground as they slipped to a 2-1 defeat at Sao Paulo.
The day's other game saw bottom club Atletico Goianiense draw 1-1 with Guarani.