Eredivisie leaders PSV were forced to settle for a point in a 1-1 draw at Heracles on Sunday.
Fred Rutten’s side had the chance to move five points clear at the top of the league with a win in Almelo and they looked on their way after just 19 minutes.
Jetro Willems provided the assist for Zakaria Labyad to score the opener and it was an advantage they took into the half-time break.
But Heracles salvaged a point when Everton struck in the 76th minute.
Ajax’s poor season continued as they were stunned 2-0 at home by lowly Utrecht.
Edouard Duplan netted on 40 minutes after a howler from Ajax goalkeeper Kenneth Vermeer, and the French winger added a second after a quick counterattack in the second half.
The win was Utrecht’s first away in any competition since September.
Ajax have dropped to sixth in the table following their loss, with 34 points from 20 games.
Meanwhile, goals to Otman Bakkal and Guyon Fernandez helped Feyenoord to a 2-0 triumph at NEC Nijmegen while RKC Waalwijk also won well on the road, defeating FC Groningen 3-0.
