The Cobblers’ inability to score goals was once again writ large at Sixfields, and the deficiency could now mean the writing is on the wall in terms of the team’s fate.
Results elsewhere in Sky Bet League Two on Monday were all favourable, but Northampton will soon run out of second chances.
Just three hours of football remain to be played this season, and if the team cannot work out a way to score goals in those 180 minutes then they are down.
Portsmouth, in front of a large and vocal Easter Monday crowd, were entirely for the taking.
Despite their good form going into the game, they did little to suggest during it that they are anything special, and a better team would have dispatched them with ease.
The Cobblers should at least have taken a point from the contest but did not because of the excellent performance of visiting keeper Trevor Carson and their own lack of anything remotely resembling potency in attack.
The build-up play is generally fine. Darren Carter passes well, Ricky Ravenhill blocks well and Chris Hackett is a speedy match for any left-back in the division.
But they are the proverbial jigsaw, going to pieces whenever they are in the box.
Quite what Evan Horwood must make of his team-mates is anyone’s guess.
In successive games he has played a ball into the penalty area that any good centre-forward would have tucked into the back of the net.
At Wycombe nobody was there and the ball ran between the six-yard line and the goalkeeper, who breathed a sigh of relief that no claret shirt pounced on it.
Against Portsmouth, Emile Sinclair was there but somehow - in one of the most inexplicable incidents of recent Northamptonian footballing times - failed to make any kind of contact on the ball whatsoever.
Without speaking directly to the player, it is hard to say why it happened.
There were no defenders near him and so there were no real distractions.
It has been suggested in some quarters that he pulled out of the header for some reason (although quite what that might be is an absolute mystery) and if that is true then it is a very worrying truth.
With a goal poacher in the side, the result of Monday’s game would have been very different and the fact, hard to stomach as it is, is that this is a team that does not score many goals and therefore does not win many games.
Maybe it will not win enough games to stay up.
Not that the effort isn’t there in some areas.
John Marquis almost seems to be on a one-man mission to discredit the theory that loan players don’t care about their temporary clubs.
His enthusiasm knows no boundaries and his energy is almost bottomless; often he oversteps the mark, but has the spite in him that is sorely lacking in some others.
Lessons about work-rate and commitment can be learned from Marquis.
And Ivan Toney added a youthful zest and exuberance to the forward line, throwing himself into aerial challenges with a strength not normally associated with whippersnapper first-team professionals.
Kelvin Langmead, in a brief 10-minute cameo, brought some much-needed muscle.
It has been said on countless previous occasions, but this would have been a very different season if he had been fit and available for all of it.
It still may not turn out to be a complete disaster.
But the ‘broken record review’ of this match is the same as it has been for dozens of other in a dismal 2013/14 season: that the team simply does not score enough goals.
In two weeks’ time we will all know just how costly that fair major shortcoming is going to turn out to be.
Made a big save late in the game that was the direct result of the right decision being made and his expert timing ...6
The throw-in is not the threat it once was and although this was a composed performance his distribution could have been better ...6
The stand-out performer, his return to the side was a seamless one and his ball-carrying out of defence was a key feature of the game ...7
Bad timing gave away the free-kick from which Portsmouth scored but other than that it was a sound performance in both a three and then as a conventional centre-back ...6
Taken off with a knock at half-time and to facilitate a tactical reshuffle; has performed well prior to that ...6
Made a couple of sloppy passes but on the whole this was a good performance and he consistently tried to drive the team forward from the middle ...7
Made a number of key interceptions and even got a shot away, although it was never likely to trouble the visiting goalkeeper ...6
Another good outing at left-back and for the second game running it was one of his crosses that provided the best goalscoring chance ...7
The better attacking came through Hackett, who played two or three very good crosses into the box from the right wing in the second half ...7
The story of his game begins and ends with his bizarre and inexplicable failure to make contact with a back-post header in the first half. Offered almost nothing else ...4
Plays with a relentless intensity that often leads to foul trouble but gives the opposing defenders no peace whatsoever. Unlucky not to score here ...7
IVAN TONEY (for Sinclair 46)
Added some pace up front as the like-for-like replacement for Sinclair and the forward line improved with him in it ...6
IAN MORRIS (for McSweeney 46)
Enjoyed some bright moments on the ball and was a prominent figure in the team’s efforts to get back in the game ...6
KELVIN LANGMEAD (for Ravenhill 80)
No real time to make an impact but he almost did as an emergency centre-forward. Should be used again in this role in the next two games
Not used: Snedker, Deegan, Connell, Moyo