Just over a year ago the Bulls made a dramatic comeback to win at Sixfields but needed no such heroics on Tuesday as they piled the pressure on home boss Gary Johnson.
The false dawn of two successive wins a few weeks ago has been replaced by the cold reality of three defeats on the bounce and a position firmly anchored in the bottom half of League Two.
Elder and Leslie made it an uphill climb for the Cobblers with goals inside the first twenty minutes and, despite Berahino giving the home side hope, Pell made the game safe for Hereford.
The attendance at Sixfields reflected Northampton's current plight with just 3,643 there to see another disappointing home defeat.
Reaction: "The players know that they didn't perform as individuals or as a team," Johnson told the official club website after the game.