Feyenoord crushed their city rivals Sparta Rotterdam 7-0 on Sunday to maintain their recent impressive form.
The win means that Giovanni van Bronckhorst's side have now won four of their last five games in all competitions having only won once in nine before that.
The reigning Eredivise champions raced into a 4-0 lead by the interval thanks to a brace from Tonny Vilhena and goals from Dylan Vente and Jeremiah St. Juste.
Renato Tapia, Steven Berghuis and Bilal Basacikoglu all scored in the second half to add gloss to the scoreline and send their neighbours bottom of the table on goal difference.
Ajax beat AZ Alkmaar 2-1 in another of the day's big games to cut the gap to PSV Eindhoven at the summit of the table to five points.