Aman Verma's strike gave Kettering their first win in four matches at the expense of Braintree.
Verma, Steven Meechan and Djoumin Sangare all forced visiting keeper Nathan McDonald into action in the first half.
Adam Cunnington deservedly put the hosts ahead from Sangare's cross only for the Iron to level through Sean Marks' firmly-struck effort.
The Poppies grabbed victory when Verma lashed home from George Tait's cross.
VIEWS FROM THE DRESSING ROOM
Kettering Town manager Mark Stimson tells BBC Radio Northampton:
"The players are grasping it. They've done a lot of legwork last week, and they've been in Sunday and Monday, because it was a big game tonight.
"It was a great finish by Adam Cunnington and then you wish it was over, but you know there'll be twists and turns. We didn't keep the lead for that long but full credit to the boys, we've got the reward that we deserved.
"Adam will get the plaudits but the two centre-halves were thrown together and they've done well against a good pair."
Braintree Town manager Alan Devonshire tells BBC Radio Essex:
"It's really disappointing. We've had a great run. Now we're had three defeats on the trot and it isn't good enough.
"The first half was quite even. In the second half, we were in their half most of the time. We just didn't take care of Adam Cunnington up front - that was the difference.
"We weren't patient enough and we've got to learn from it. You have a squad, so I'm not going blame people missing. The team out there is good enough to get the result."