FC United suffered their first defeat in eight games, going down to the UniBond League's form team Eastwood.
The Badgers arrived at Gigg Lane after just one defeat in 14, including the scalp of Conference big guns Wrexham in the FA Cup.
And their tight, well-organised defence proved too tough a nut for the lack-lustre Rebels to penetrate, on a cold blustery night.
The game turned on a 44th minute incident when on-loan Rotherham winger Andy Todd, through one-on-one with goalkeeper Sam Ashton, went down under a challenge from behind by Adam Carden.
Striker Ian Holmes tucked away the spot kick, and FC - unchanged from the team which came close to beating second-placed Guiseley on Sunday - had no response.