The top two in the Eredivisie remain just one point apart after leaders PSV Eindhoven and second-placed Twente both won on Sunday.
PSV recorded a 3-0 victory away to second-bottom VVV Venlo, while Twente came from behind to beat fourth-placed Groningen 2-1.
Fullback Wilfred Bouma put PSV ahead 13 minutes in at De Koel, before a goal either side of half-time effectively sealed the win for the visitors.
Dutch international Jeremain Lens struck in the 45th minute to put PSV 2-0 up and Atiba Hutchinson made it 3-0 just 60 seconds into the second half to secure the points.
Twente had to do it the hard way after falling behind in the first half at Groningen’s Euroborg Stadion.
Tim Matavz gave the hosts the lead in the 33rd minute, but an equaliser from Marc Janko just seven minutes later ensured Twente would go in level at the break.
Janko then grabbed the winner for the visitors with nine minutes left in the second half.
The Austrian striker should have claimed his hat-trick, but missed a penalty in the 84th minute.
PSV remain top with 44 points, one point ahead of Twente and six clear of Ajax, who fell further off the pace after a 3-0 defeat away to Utrecht.
Two goals in the space of two first-half minutes from Edouard Duplan put seventh-placed Utrecht firmly in control at the New Galgenwaard Stadium.
Ismo Vostermans netted a third with seven minutes to go to make absolutely sure for the hosts.
Defeat leaves third-placed Ajax six points off PSV and five behind defending champions Twente.
Elsewhere, goals from Jimmy Hempte, Pa-Modou Kah and Morten Skoubo gave Roda JC a 3-0 win at home to third-bottom Excelsior, who finished with 10 men after the 64th-minute dismissal of Kaj Ramsteijn.