Chris Wilder felt his attack did not do enough against Burton Albion as the Cobblers were beaten at home by the Brewers.
Town were sunk 2-1 by Albion, who scored through former Sixfields loanee Jacob Blyth and midfielder Alex MacDonald, who netted an excellent free-kick four minutes from time.
It is a second successive loss on home soil for Northampton, who were beaten 5-4 on their previous outing at their own ground, by Accrington.
Winger Kaid Mohamed missed an open goal midway in the first half, which was to prove costly, and Wilder said there has to be more ‘spark’ from his attacking players.
“Missed chances have cost us, especially in the first half,” he said. “They made it difficult for us in the second half and of course they are going to do that, that’s what it’s all about.
“They sat deep and we couldn’t find a way through. Our front four have been good enough for the majority of the season and they weren’t today.
“When you want to win games you look to your front four to spark and they didn’t for us in this game.
“Burton defended manfully and forced us to change our shape because there wasn’t enough room in behind.
“In games like these I think if you score the first goal then you go on to win it and there’s no doubt we should have scored the first goal today.
“We had two of the clearest opportunities in the game by a million miles and if we go in 1-0 up then we go on to win the game.
“Burton don’t come from behind to win games a lot with the way they set up.”