The Sixfields clash pits the team one off the bottom of League Two with a side just one place from the summit but, despite their lowly position, the Cobblers go into the game in good spirits.
Aidy Boothroyd's arrival has had a positive effect on his side and confidence will have been boosted further by a first win under the new boss at Morecambe last weekend.
That optimism will be tested to the full by Southend however with the Shrimpers just a point behind Crawley in the race for the title.
Having completed deals for midfielders David Martin and Michael Timlin last week, United manager Paul Sturrock is set to sign Bolton's young striker Jack Sampson on loan in time for the weekend.