AZ Alkmaar left it late to see off Roda JC 1-0 on Wednesday night and move nine points clear at the top of the Eredivisie table.
Mounir El Hamdaoui struck the winner with 14 minutes remaining to earn AZ their 10th home win in a row.
The hosts' closest challengers are now FC Twente, who beat NAC Breda 4-1 tonight to move above Ajax in the table.
The Enschede side were 2-0 up by half-time thanks to goals from Marko Arnautovic and Peter Wisgerhof, and that became 3-0 through Eljero Elia on the hour mark.
Fouad Idabdelhay pulled one back for NAC two minutes later, but substitute Romano Denneboom rounded off the scoring for in stoppage-time for Steve McClaren's men.
FC Groningen moved up to fifth with a 2-0 win at home to 10-man NEC Nijmegen.
NEC had Ramon Zomer sent off in the 25th minute for a foul on Marcus Berg in the area and Berg composed himself to dispatch the resulting penalty.
Koen van de Laak sealed the points just after the hour mark.
Towards the other end of the table, Feyenoord secured a 1-0 derby victory over Sparta Rotterdam thanks to Diego Biseswar's early goal.
Cedric van der Gun's bagged a hat-trick to give FC Utrecht a 3-0 win over second bottom De Graafschap.