Leon Archer pounced on a defensive mistake to put the visitors ahead in the 26th minute and they stayed in front until the hour mark, when a header by Jordan Cox (pictured by Mikey Cartwright) eluded the grasp of keeper Obey Murefu.
Cox also nabbed the winner, his 19th league goal, from a cross by newly-arrived substitute Jack Stephenson in the 83rd minute.
Waltham Abbey moved up one place to 15th with a 3-0 victory at Waltham Forest and, with their season only halfway complete, they still feel they can challenge for a promotion place if they profit from their games in hand.
The goals all came in a 13-minute spell in the first half. Joe Pearman opened the scoring after 25 minutes and that was followed by strikes from James Peagram and Dean Green.
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