Heerenveen overcame Willem II 1-0 in their Eredivisie clash at Abe Lenstra Stadion on Friday night.
Sam Larsson scored the only goal of the game on 40 minutes to secure the victory and lift his side onto 40 points in eighth place with Willem II left in 11th with 36 points.
Pele van Anholt missed early on as the visitors came firing out of the blocks.
Kostas Lamprou denied Yuki Kobayashi after a number of half chances for both sides
Thom Haye was well wide as Larsson fired just past a post midway through an evenly-contested first half.
Lamprou then did well to stop a Van Amersfoort effort from ending up in the back of the net before Larsson finally broke the deadlock on 40 minutes.
Heerenveen looked the more likely team to find the next goal, with Martin Odegaard seeing his effort fly wide right of the target as Fran Sol was equally unsuccessful at the other end.
Arber Zeneli forced another fine save with 68 minutes gone while Larsson's late shot was easily saved before Reza Ghoochannejhad had a good effort stopped from ending up in the bottom right corner of Lamprou's goal for the last chance of this absorbing contest.