There was more Sixfields misery for the Cobblers on Saturday when they slumped to a fifth successive home defeat despite a much-improved performance, losing 2-1 to title-chasing Scunthorpe United after a keenly-contested affair.
Again it was a late goal which sunk Northampton as Josh Morris' superb strike seven minutes from time denied the home side what would have been a deserved and crucial point in their battle to avoid being sucked into a relegation fight.
Incoming boss Justin Edinburgh was reduced to a watching brief for this game as he used the visit of Scunthorpe as an opportunity to assess his new players who were under the guidance of caretaker Paul Wilkinson.
The high-flying Iron were always going to provide a stiff test for the Cobblers but Edinburgh would have been encouraged by what he saw, especially in the first-half when his new side bettered a team who are in the mix for both the title and promotion, even after Kevin Van Veen had nodded the visitors ahead.
Prior to going behind, Alex Revell saw three wonderful chances go begging,and he would make amends for those misses on the stroke of half-time when finally getting on the score sheet by squeezing home a header at the near post.
Playing with more gusto and purpose than recent showings at Sixfields, Northampton had deserved that goal and again they promised much in an end-to-end second-half, however a lack of creativity combined with some wayward finishing would prove their downfall.
Scunthorpe always carried a threat and it was the in-form visitors who stole the spoils through Morris' fine strike.
Although Town remain 16th, results elsewhere went again them on Saturday as wins for struggling Shrewsbury, Chesterfield, Oldham and Bury means the gap back to the bottom four is now just five points.
With a new manager in position and a favourable run of fixtures to come, the next few weeks will potentially be a season-defining period of the season, one way or the other, as Northampton bid to end their wretched run of form which has seen them lose 10 of their last 12 and last five in the league at Sixfields.
Wilkinson's team selection included a debut for new signing Neal Eardley at right-back as seven players survived the 5-0 mauling at Bristol Rovers seven days earlier.
Those to drop out of the team were Paul Anderson, Rod McDonald, Greg Wylde and Harry Beautyman, as in came Eardley, Lewin Nyatanga, John-Joe O'Toole and Marc Richards.
With Matty Taylor starting on the left wing, Wilkinson opted for a straightforward 4-4-2 in what would be his sole game in charge but despite there being a noticeable buzz around Sixfields following the appointment of a new manager, an error-strewn opening 15 minutes provided little reason for either side to get excited.
Richards had a shot blocked and Taylor's crisply-struck free-kick was tipped over by Luke Daniels for the hosts, while Van Veen planted his free header wide from 10 yards as the visitors enjoyed more possession without overly threatening.
But a low-key start then burst into life with a sudden flurry of action as Northampton, specifically Revell, had three excellent chances in the space of 30 seconds.
Daniels came to the rescue for Scunthorpe on two occasions, first pulling off a fine save to deny Revell's first-time volley from Taylor's exquisite pass before then parrying away the follow-up effort, before captain Stephen Dawson cleared the Cobblers striker's third effort from off the line.
That period of pressure encouraged the home crowd and a rejuvenated Northampton were sensing the opening goal, but a lackadaisical piece of defending at the other end instead allowed United to hit the front.
Scunthorpe had played second fiddle for much of the opening quarter but they went ahead when Dawson, moments after rescuing his side at one end, broke down the right and crossed for Van Veen who, again given far too much space inside the box, this time made no mistake, placing his header into the far corner.
Taylor immediately had the opportunity to reply for Town but his free-kick from 20 yards hit the wall and harmlessly deflected behind for a corner.
Things went a bit flat after that as the sound of the referee's whistle began to dominate proceedings as needless fouls and sloppy mistakes prevented either side from building much pressure.
However, with half-time approaching, Town, playing with more purpose and intent than recent weeks, gradually built up a head of steam with a sustained spell of decent pressure.
And that good play was rewarded in the nick of time. Having worked the ball out wide to the left, Taylor found enough space to whip in a wicked cross and Revell was there to stoop low and squeeze a header into the net via the hand of a despairing Daniels.
That hauled the Cobblers back on level terms and not even the staunchest of Scunthorpe supporters could deny the hosts had warranted at least a share of the scoreline going into half-time.
Unlike in previous games at Sixfields this season, Northampton came out in the second-half with the intent to press United and match the visitors stride-for-stride as the high-flyers weren't allowed to dominate possession like other away sides have.
That positive approach almost paid dividends too when Scunthorpe failed to deal with O'Toole's cross which almost squirmed into the net.
United went even closer to scoring at the other end when Tom Hopper met Jordan Clarke's deflected cross and hit the post before Van Veen dragged a shot comfortably wide.
It was then Northampton's turn to rattle the woodwork in what was becoming an end-to-end, entertaining second period when Zander Diamond powered his free header onto the post from Taylor's corner.
Another Taylor set-piece brought another free header for Diamond and again he failed to hit the target as the Cobblers continued to give as good as they were getting had and rattled their title-chasing visitors.
And they also continued to create chances with Richards the latest culprit to fluff his lines when miss-kicking his shot from eight yards out.
Scunthorpe too posed a threat, particularly through the pace of Duane Holmes, and for the third time in the second-half the woodwork was rattled when this time Josh Morris' well-hit free-kick cannoned against the crossbar.
That was followed by an excellent Smith save to deny the dangerous Holmes before United boss Graham Alexander introduced former Cobbler Ivan Toney for the final 10 minutes.
A fine piece of defending from David Buchanan prevented Holmes from getting clean through on goal before the United winger was denied by Smith.
With the clock ticking down, both sides were looking dangerous, and there was to be a late sting in the tail - and unfortunately for the Cobblers it was the away side who got their noses in front with a moment of magic.
Having picked up the ball 40 yards from goal, Morris drove forward and took his time before unleashing a stunning strike that curled beyond Smith and into the top corner.
It was a cruel blow for the Cobblers who had competed so well but were unable to lift themselves off the canvas after Morris' fatal blow as they struggled to mount any kind of response, allowing United to leave Sixfields with all three points.
Cobblers: Smith, Eardley, Diamond, Nyatanga, Buchanan, Hoskins, O'Toole, Boateng (McCourt 79), Taylor, Revell, Richards (c)
Subs not used: Cornell, McDonald, Hanley, Beautyman, Wylde, Iaciofano
Scunthorpe: Daniels, Wallace, Clarke, Dawson (c), Toffolo, Mantom, Goode, Holmes (Crooks 85), Morris, Hopper (Davies 63), Van Veen (Toney)
Subs not used: Williams, Anyon, Adelakun, Sutton
Referee: Graham Horwood
Scunthorpe fans: 499