Ajax are up to third in the Dutch Eredivisie after a 4-2 victory at Willem II on Sunday, while Feyenoord also won.
Ajax resisted a spirited challenge from Willem II to claim their away win.
Siem de Jong registered his seventh goal of the season in the 11th minute, with Danny Hoesen promptly doubling Ajax's lead three minutes later, and it looked like Frank de Boer's men had opened a clear route through to a sixth straight league win.
But Aurelien Joachim halved the deficit just two minutes after Hoesen's strike, with Genaro Snijders notching in the 28th minute to ensure the scores were level going into the break.
Ajax became more and more frantic as their hosts held them at bay throughout a frustrating second half, but Niklas Moisander gave De Boer's men the lead once again in the 72nd minute.
Willem came close to salvaging the late equaliser that would have kept Ajax in fourth place but visiting substitute Jody Lukoki squeezed in a final goal to confirm the Amsterdam club's ascent.
Ajax's victory curbed Feyenoord's own climb up the table after ADO Den Haag's Tjaronn Chery handed Ronald Koeman's men a 3-2 victory with his late own goal.
On-loan Parma striker Graziano Pelle made the most of Bruno Martins Indi's pass to score his 14th goal of the season with 15 minutes gone, but Den Haag levelled immediately.
Mike van Duinen was well-placed to turn home Chery's cross and the visitors looked good for parity going into the break, only for Pelle to push Kenneth Omeruo in the back, allowing Lex Immers to edge Feyenoord back in front from the spot.
A mad minute threw the game wide open when play resumed, Danny Holla converting a penalty when Martins Indi brought Van Duinen down in the area - an offence for which he saw a red card. Tom Beugelsdijk soon walked for elbowing an opponent and both sides were down to 10 men.
And four minutes from time it fell to Chery to hand Feyenoord all three points with a headed own-goal. Feyenoord remain in fifth place thanks to Ajax's success in Tilburg.
Sander Duits denied Vitesse Arnhem the chance to draw level on points with second-placed FC Twente - and keep Ajax at bay - as his stoppage-time goal earned RKC Waalwijk a point from a 2-2 draw.
Wilfried Bony put Vitesse ahead after just eight minutes at the GelreDome and it took Teddy Chevalier until the 78th minute to equalise for RKC.
The hosts were unfazed, though, and Simon Cziommer fired what appeared to be the winner nine minutes from time, only for Duits to earn RKC point three minutes into time added on.
Elsewhere, FC Utrecht opened a five-point gap over seventh-placed NEC NijmegenHeerenveen.
Both sides drew a blank in the first half but De Kogel seized on Jacob Mulenga's pass to put Utrecht ahead in the 66th minute. The 21-year-old striker completed his brace four minutes later before Alfred Finnbogason halved the deficit from the penalty spot.
But Heerenveen could not force an equaliser and Mulenga, who had previously had a goal ruled out for offside, made the hosts' points safe with his 89th-minute strike.