The Cobblers were well below their best at Hartlepool United on Tuesday night as their winning streak disappeared in the Teesside fog.
Town were poor in a poor game settled by a poor goal.
Their key players, especially in attack, never got going and it was an off-night for at least half of the team.
They did not look like a side who had beaten five opponents on the bounce and were a shadow of the effervescent outfit which shredded Accrington 10 days previously.
But still, it was a game settled by a single mistake rather than an intelligent piece of play or a tactical masterstroke.
Lee Collins was the man in the wrong, but it should be noted that other players had given Matt Duke passes back prior to his error, a worrying strategy considering the goalkeeper’s trouble with his kicking on the night and the quality of the pitch.
The Hartlepool fans may be the best ‘12th man’ in the division, and although there were only 2,700 in attendance on Tuesday night it sounded more like at least twice that many as they backed their team vociferously from the start.
With the lead, they grew even louder and their influence told on the referee (as it did last season), who gave 17 fouls against the Cobblers compared to just six in their favour.
But the referee was not the reason for the defeat and although it was sealed by a mistake it would be unfair to pin the blame entirely on the defensive end of the team.
Lawson D’Ath and Ricky Holmes just could not pick up the rhythm of the game right from the start and that impacted on John-Joe O’Toole, who needs pace either side of him to allow his passing game to flourish.
It was the right decision to withdraw them during the game and freshen things up, and you imagine that will be an area Chris Wilder looks at in his preparations for the trip to Mansfield on Saturday.
In front of those two, Marc Richards was often isolated and his one good goalscoring chance was blocked by David Mirfin, while behind them Jason Taylor was not the effective hunter-gatherer he has been and Joel Byrom was in and out of the game as a creative force.
The best play came from the full-backs, who were used as wing-backs when D’Ath and Holmes were taken off and the team changed to a 3-5-2 system.
That led to a spell of pressure and several good-quality crosses into the box from wide areas, but Northampton were unable to capitalise on them.
Of course, seasoned supporters will tell you that it’s all part of the Cobblers’ not-so-rich tapestry that they would lose such a game, and there was a grim inevitability about it as it all unfolded.
Hartlepool were unrecognisable from the side which was routed 5-1 at Sixfields earlier in the season and the win will give them added belief that they can complete a great escape and retain their league two status.
Whether the Cobblers are at that level next season remains anybody’s guess, but if they are to stand any chance at all they cannot afford many more no-shows like this one.
Kicking game was a little off, possibly because of the conditions, and he made a couple of good saves in the second half ...7
Did well as a right-back in the first half and then was one of the team’s best attackers after the switch to the wing-back system ...7
Was an aggressive force in both boxes and perhaps did not deserve to be on the losing side. Had a late header well saved by Flinders ...6
Will remember the game mainly for his costly mistake but was fine either side of it and did his best to atone in the second half, carrying the ball great distances out of defence ...6
The pick of the players on the night - executed his defensive duties well and put in the best crosses from wide areas ...7 STAR MAN
Didn’t reach the amount of second balls he usually does in what was pretty much just a dogfight in central midfield ...5
Because everything in the middle of the park was so rushed, he was unable to play his usual passing game and his influence on the contest was sporadic ...5
Had two good runs in the first half and had his defender frightened both times but was not the attacking force he has been this year ...5
Forced to feed off bits and pieces because of the Cobblers’ inability to get a foothold in Hartlepool territory and seemed generally below par ...5
Did his best to puncture the home defence with some long runs but was often double-marked and didn’t really make any headway ...5
His only real chance of the game came in the first half and was well blocked by Mirfin, and his team-mates were often too far away from him for his true influence to tell ...5
IVAN TONEY (for D’Ath 57)
Found himself in immediate and plentiful foul trouble (which was only partly his fault) but added a bit of physical presence to the attack ...6
BEN TOZER (for Holmes 57)
Slotted in well on the right of a back three and - like Collins on the other side - got forward to create some attacks from deep ...6
CHRIS HACKETT (for O’Toole 74)
Seemed to play all three attacking midfield positions in the 16 minutes he was given but Hartlepool were set deep by that point and snuffed him out ...5
Not used: Carter, Bodin, Snedker, Newey