John-Joe O’Toole’s early opener was cancelled out by Jason Demetriou’s penalty but Matt Grimes scored from the spot before Alex Revell’s late third lifted the Cobblers to within two points of safety as Southend suffered a sixth league defeat in seven.
The first half was short on quality and that was epitomised by Northampton’s opener in the 19th minute.
After Mark Oxley beat away Ash Taylor’s header, Harry Kyprianou’s attempted clearance cannoned off Matt Crooks and fell for O’Toole to guide the ball into the bottom corner.
The lead lasted just seven minutes, however, as Taylor collided with Stephen McLaughlin in the box and Demetriou slotted home the resulting spot-kick.
But the visitors were behind again early in the second half when Chris Long was fouled by Kyprianou for a penalty which was dispatched confidently by Grimes.
Cobblers debutant Hildeberto Pereira hit the crossbar moments after coming on before he set up the game-clinching third, slipping in Revell who found the bottom corner.
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Former Swansea caretaker boss Alan Curtis believes Carlos Carvalhal deserves great credit for the impact he has had at the club.
West Ham have issued life bans to five pitch invaders who came onto the playing surface in the defeat to Burnley last time out.
Brighton centre-half Shane Duffy says his game has come on leaps and bounds thanks to Chris Hughton and Martin O'Neill.
Bournemouth midfielder Lewis Cook says he is ready to take his chance with England should he be handed his senior debut.
Tottenham will have to make a massive offer to land Wilfried Zaha, according to former Crystal Palace chairman Simon Jordan.
Nigel Clough believes keeping Burton in the Championship this season will surpass the achievements of last term's survival.
Garry Monk has challenged his Birmingham players to maintain the high standards they set when beating Hull in their last league game.