Harry Anderson scored the only goal of the game after 38 seconds, collecting a short back pass from Fraser Horsfall and firing home from a tight angle.
Town battled hard to get back into the game, and went on to hit the woodwork twice, but couldn't find an equaliser.
Here are our player ratings from Sixfields.
13. Chanka Zimba
The Cardiff City loan striker was thrown on for the final 20 minutes but failed to make an impression. Had one shot from range that flew high and wide... 5 Photo: Pete Norton
14. Bez Lubala
Sent on in the closing minutes as a last throw of the dice... n/a Photo: Pete Norton
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