Willem II Tilburg give Heerkens heave-ho
Heerkens joined Tilburg last July but they earned just two points from the first 15 league matches. They now have 12 points and prop up the division, five points adrift of VVV Venlo.
The clubs said in a statement the decision was not only aimed at avoiding relegation this season but building for the next campaign.
Tilburg will travel to face Feyenoord on Sunday.