The game between ADO Den Haag and Vitesse Arnhem was abandoned on account of crowd trouble, while Ajax were held at home by Twente.
Vitesse had raced into a 3-0 lead courtesy of goals from Danko Lazovic, Anduele Prijor and Etienne Esajas when ADO fans stormed the pitch 23 minutes from time to protest against the club's poor results.
Police failed to restore order and the decision was take to abandon the contest and KNVB officials are sure to take a dim view of proceedings.
Ajax lost ground on PSV Eindhoven in the title race after being held at home by Twente.
PSV threw down a marker with a win over Excelsior on Saturday, but Ajax failed to respond at home to Twente.
Orlando Engelaar volleyed the visitors ahead on eight minutes and it took a fine free kick from Wesley Sneijder on 48 minutes to bail Ajax out of trouble.
Groningen continue to impress and they ran out 4-1 winners over Willem II.
Erik Nevland fired the home side into a two-goal lead but Willem II briefly threatened when Anour Hadouir reduced the arrears 20 minutes from time.
However, late goals from Yevgeny Levchenko and Glen Salmon ensured Groningen ran out comfortable winners.
Ricky Kruys and Gregoor van Dijk were on target as Utrecht proved too strong for Roda JC.