Ola John and Willem Janssen scored twice for Twente Enschede in a 6-2 romp at Utrecht, although the match was halted for 15 minutes in the second half after crowd disturbances.
Bas Dost headed home the opener for Heerenveen after 14 minutes but six minutes later Brett Holman and Jozy Altidore combined for the U.S. international to level.
Rajiv van la Parra restored the home side's lead after a well-executed counter-attack on the half-hour and goals from Filip Djuricic and Ramon Zomer in the first three minutes of the second half settled the match before Luciano Narsingh added a fifth.
Alkmaar remain on 34 points after 14 matches, three ahead of PSV, who have played 15 while Twente are a point further back.
PSV were overpowered by resurgent Feyenoord who led through Sekou Cisse's opener late in the first half after he finished off his own interception. Ruben Schaken doubled the lead with a tight-angled shot early in the second half.
Feyenoord are fifth with 27 points, on goal difference behind Ajax Amsterdam, who beat Excelsior 4-1 on Saturday.
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