Amsterdam, Netherlands – Ajax fell further off the title pace 0 home defeat against Utrecht.
The loss is the second straight for the Amsterdam side and drops them eight points back of leaders PSV Eindhoven, while Utrecht moves seven points clear of the bottom three.
Utrecht took the game to the hosts from the start and found the opening goal five minutes before halftime when Alexander Gerndt's cross was spilled by Ajax goalkeeper Kenneth Vermeer, allowing Duplan to follow up the play and knock home the loose ball.
Ajax struggled to get back into the game and Duplan put the result beyond reach in the 78th minute when Frank Demouge played Duplan into the penalty area on the right and he beat Vermeer with a shot inside the far post.
Twente had a chance to join PSV at the top of the league but its match at De Graafschap was postponed due to poor weather conditions, while PSV was only able to pick up a point at Heracles as the hosts got a goal from Everton in the 76th minute to snatch a 1-1 draw.
Feyenoord moved into the top five after a 2-0 victory at NEC on Sunday that saw Otman Bakkal and Guyon Fernandez net goals for the winning side, while RKC Waalwijk scored twice in the opening five minutes of a 3-0 win at Groningen.