Calling the dismissal of Abdul Osman 'harsh', Sampson was nonetheless delighted with how his players then managed to contain the highflying Valiants.
'They did everything we asked of them,' he told the official club website after admitting that he made the decision to try and stifle the visitors once the Cobblers had been reduced to ten men.
'I think that decision was justified.'
Northampton now travel to bottom of the table Barnet next weekend looking to continue their recent upturn in fortunes.