A second-half penalty from Kevin van Veen, his 10th goal of the season, helped Cobblers return to winning ways with a hard-fought 1-0 victory over 10-man Crawley Town at the Broadfield Stadium on Saturday.
The football in the first-half matched the gloomy and drizzly conditions in West Sussex as both teams laboured in a scratchy affair, but the match-defining period came just after half-time when Crawley's Ollie Palmer pressed the self-destruct button.
His ill-judged challenge gifted the Cobblers a penalty and allowed van Veen to reach double figures for the season, and then moments later he was given his marching orders after clashing with Aaron Pierre.
Those two incidents gave the otherwise below-par visitors a huge leg-up in pursuit of victory, and while it was far from a vintage performance, the three points will be welcomed by manager Keith Curle after his side had gone five games without a win.
The Cobblers are up three places to 14th in Sky Bet League Two, still eight points off the play-offs.
Curle stuck with three at the back in West Sussex but made six changes from Tuesday's penalty shoot-out win at Cambridge, one of which saw Dean Bowditch come in for his first league appearance in over two months,
Shay Facey also returned and there was also a welcome return to the bench for fit-again Matt Crooks, but fellow midfielder John-Joe O'Toole missed out completely.
Cobblers had the better of a scrappy start but Crawley wrestled back the ascendancy and were first to threaten when, on 16 minutes, Panutche Camara found himself with enough time and space to send a fine curling effort smacking off David Cornell's crossbar.
There was little else to write home about in a desperately disappointing first-half that was mostly devoid of any serious goalmouth action.
While Camra's fine attempt remained Crawley's clearest opening, Town had their best chance towards the end of the half when Facey's cross was missed by an unmarked Sam Foley and dropped to David Buchanan at the back post, but his shot was blocked at close quarters.
It appeared there'd be more of the same after the break, but the game came alive seven minutes into the second-half as Palmer pressed the self-destruct button and Northampton were the grateful beneficiaries.
His first act of self-harm was to needlessly barge over Pierre in his own penalty box and give away a penalty, which van Veen easily dispatched by sending Glenn Morris the wrong way for his 10th of the season.
It went from bad to worse for Palmer and Crawley moments later when the red mist descended and he clashed with Pierre again, sent off after the referee deemed he had landed an elbow on Town's centre-back.
Curle then introduced Crooks for Foley as Cobblers set about making their extra man count, although Crawley weren't about give up as Reece Greco-Cox shot wide on the edge of the box.
Cornell fumbled a powerful long-range shot and Camara fired wide from the edge of the area while Morris kept out Facey at the other end as the game became more and more stretched.
Increasingly unhappy home supporters were up in arms again with eight minutes to go when Danny Bulman, through on goal, fell to ground under a challenge from Ash Taylor, but the referee waved away appeals for a foul.
Substitute Daniel Powell squandered an opportunity to settle nerves in stoppage-time, denied by the legs of Morris, but bar a late free-kick that sailed harmlessly over the crossbar, Town saw out six minutes of injury-time to make a winning return.
Crawley: Morris, Payne (Nathaniel-George 78), McNerney, Poleon (Grego-Cox) , Gambin, Francomb, Maguire, Bulman (c), Camara, N'Gala, Palmer
Subs not used: Mersin, Young, Doherty, Vincelot
Cobblers: Cornell, Taylor, Turnbull, Pierre, Facey, Buchanan (c), Foley (Crooks 57), McWilliams, Bowditch, Hoskins (Powell 80), van Veen (Morias 80)
Subs not used: Ward, Bridge, Waters, Williams
Referee: Craig Hicks
Cobblers fans: 499