Former Manchester United defender Daley Blind was one of two Ajax players to score a hat-trick as they thrashed De Graafschap in the Eredivisie.
Blind scored all his goals in the second half, including a long-range thunderbolt into the top corner.
Morocco international Hakim Ziyech also scored three times as the hosts ran riot at the Johan Cruyff Stadium.
Ex-Southampton midfielder Dusan Tadic opened the scoring with Noussair Mazraoui also on the scoresheet.
Erik ten Hag’s side have lost one and drawn one of their 16 league games this season and are two points behind champions and leaders PSV Eindhoven.
Mark van Bommel’s men, who have lost once, stayed top after thrashing Hercales 4-0 on Saturday.