Mansfield's relegation worries increased significantly after a woeful performance against Bury.
The hosts went ahead with barely 10 minutes played as skipper Paul Scott rose highest to head in Elliott Bennett's free-kick.
The Shakers doubled their lead after 37 minutes when Bennett set up Adam Rooney to smash home from 15 yards.
Stephen Dawson struck the post as Mansfield looked for a second-half recovery but it was not to be.
Not the case Chase Richardson didnt play him Rooney asked why Richardson said he could go back if he didnt like it so Rooney did so, because he didnt want to sit on his rump at Chesterfield