NEC Nijmegen poured misery on winless neighbours Vitesse Arnhem by coming from behind for a 3-1 derby victory on Sunday.
NEC, whose own season only ignited prior to the international break, made it two wins out of two as they recovered from Nicky Hofs' first-half strike to win with goals from Arek Radomski and Saidi Ntibazonkiza either side of Youssef El-Akchaoui's penalty in the second half.
Willem II heaped more misery on Feyenoord, inflicting a fourth defeat in six games on the Rotterdam giants to leave them just outside the relegation places in the Eredivisie.
In a scrappy game, Frank Demouge got the only goal in the 23rd minute.
AZ Alkmaar moved up to third place in the Eredivisie as Mounir El Hamdaoui's double gave them a 2-0 win to condemn De Graafschap to their third defeat in a row.
The Moroccan forward struck just before half-time and then added a second after 59 minutes to ensure the victory, which extended their four-game winning streak.
Sparta Rotterdam finally got their campaign off the ground as they recorded their first win of the season against FC Utrecht.
Charles Dissels scored the only goal of the game in the 18th minute and the hosts clung on to take all three points.
On Saturday, NAC Breda moved to the top of the Eredivisie table with a 2-1 home win over defending champions PSV Eindhoven. An own goal from PSV captain Timmy Simons in the 13th minute put the hosts in front and Matthew Amoah doubled the lead three minutes from time before Ibrahim Afellay's injury-time consolation for the visitors.
Groningen suffered their first defeat of the season after going down 1-0 at Ajax to slip to second, two points behind the new league leaders.
Defender Presas Oleguer proved to be the match-winner with a header eight minutes before half-time.
Also on Saturday, Heerenveen scored a late equaliser in a 2-2 draw with Roda JC, and Heracles' unbeaten record came crashing down at FC Twente with two goals in the final 10 minutes consigning them to their first league defeat of the season.