PSV beat Graafschap 4-1 to stay at summit
Dries Mertens (pictured) converted an eighth-minute penalty to open the scoring before Ola Toivonen, Tim Matavz and Jeremain Lens settled the match before the break.
Gil Vermouth gave the visitors a consolation goal from close range in the 52nd minute.
PSV have 45 points from 21 matches and are ahead of AZ Alkmaar, who beat Excelsior Rotterdam 2-0 on Saturday, on goal difference.
Heerenveen moved into third place with 40 points following a 1-0 win at 10-man RKC Waalwijk, with Rajiv Van la Parra scoring, and are ahead of Feyenoord on goal difference.
Feyenoord's John Guidetti deflected in a header after 12 minutes to open the scoring in the 3-1 home win over Vitesse Arnhem. He doubled the lead from the penalty spot before Nick Hofs converted another penalty to pull one back.
Guidetti, 19, then sealed the win seven minutes before time with his 17th goal of the season to complete his third hat-trick in five matches.
Twente Enschede, beaten 3-2 on Friday by Heracles Almelo, slipped to fifth with 39 points and a game in hand.