Dartford conceded an 89th-minute winner at Alfreton on Saturday, having twice taken the lead.
Ryan Hayes, pictured, scored from just inside the area to give Tony Burman’s side the advantage after three minutes, but Alfreton equalised in first-half injury-time through Danny Meadows' header.
Darts went back in front when Nathan Collier headed home Hayes’ 59th-minute cross.
Visiting keeper Marcus Bettinelli made a superb save from an Ashley Worsfold strike but was beaten on 74 minutes when Anton Brown finished Nathan Arnold’s pass.
An entertaining match went Alfreton’s way when Meadows netted his second.
The defeat leaves Dartford eighth in Blue Square Bet Premier.
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