AZ Alkmaar ensured they would remain top of the Eredivisie this weekend with a 1-0 home win over RKC Waalwijk today. Johann Gudmundsson scored the only goal of an otherwise poor match after 49 minutes to keep Gertjan Verbeek\'s side clear of the chasing pack. Ajax remain their closest challengers, a point behind, after beating title rivals PSV Eindhoven 2-0. The two goals came inside seven second-half minutes, with Ismail Aissati opening the scoring (56) and Siem de Jong adding a penalty. Three goals in 19 second-half minutes gave Feyenoord a 3-0 win at bottom side De Graafschap that keeps them on the fringes of the title race. John Guidetti, Ruben Schaken and Sekou Cisse all scored for the Rotterdammers to keep them five points behind AZ. Heracles Almelo capped a memorable week with a home win over ten-man FC Utrecht to further ease their relegation worries. After president Jan Smit hailed the midweek 4-2 KNVB Beker semi-final win at AZ Alkmaar as the \"high point in the history of the club,\" the Heracles players ensured there was no league hangover today. Samuel Armenteros fired them ahead after just three minutes and while Cedric van der Gun levelled on 54 minutes the game turned on Alje Schut\'s dismissal soon after. Ninos Gouriye ensured they made full use of the advantage as he struck a double in the final ten minutes to move Heracles eight points clear of the relegation play-off zone.