Boothroyd was left to lament 'five minutes of madness' as Town's slow upward progress of recent weeks was undone just before half-time in the weekend game at Oxford where two goals for the hosts secured them the three points.
The boss tried to hard remain upbeat afterwards, believing that his side are on the way up following their poor start to the season.
"The effort is there, the willing is there. Unfortunately, the concentration for those five minutes wasn't there.
"But we'll come through it, we'll climb. The signs are there and the work ethic is there."
Dagenham were beaten 2-1 at home by Cheltenham on Saturday to halt their own recent run of good form. Prior to that game, manager Wayne Burnett had said: "We are a work in progress but I like to think we are slowly getting there."
The Daggers last two away games show the danger they can pose with a 2-1 win at Accrington being followed by a 5-2 triumph at Southend United in the Johnstone's Paint Trophy.
Northampton can take comfort, however, from a 100% against their next opponents having won all six of the meetings to date.
Source: Cobblers Mad