Cobblers crashed out of the Carabao Cup at the first time of asking when they lost 7-6 on penalties after their first round tie with Wycombe Wanderers ended 1-1 at Adams Park on Tuesday.
Randell Williams' header five minutes into the second-half looked to have Wycombe on course for the second round until substitute Sam Hoskins popped up with an 82nd-minute equaliser moments after the visitors had missed a penalty.
That took the tie to penalties and it was Wycombe who prevailed in a lengthy shoot-out when Adam El-Abd calmly converted after Jordan Turnbull had seen his effort well-saved.
During the game itself, the first-half was short on clear-cut openings despite plenty of attacking intent from both teams but Cobblers again went into their shell once behind and despite Hoskins' crisp finish late on, Dean Austin's men saw their wait for a first win this season extend to three games ahead of a return to league action on Saturday.
Austin made nine changes in all from Saturday's draw at Carlisle but he still fielded a strong-looking team that included Cobblers debuts for goalkeeper Lewis Ward and striker Junior Morias and a return from injury for right-back Shay Facey.
Ward was given an early test in a sprightly start to the game when he showed assured handling to hold onto Craig Mackail-Smith's fizzing low shot while Billy Waters had two half chances at the other end but neither troubled home stopper Yves Ma-Kalambay.
Waters partnered Morias in a 4-4-2 but Town had to be on their guard in defence when Facey raced back to clear Mackail-Smith's effort off the line after he had dinked over Ward having escaping the visting back four's attention.
A brief lull in the action was followed by a busy end to the opening 45 minutes as a clear opening fell Jack Bridge's way on the half-hour mark when his free header, the product of good work from Waters and Dean Bowditch down the left, was not directed well enough and Ma-Kalambay could punch away.
The visitors were guilty of sloppiness though and they were twice fortunate not to be punished for erratic passing when Ward gathered Nick Freeman's long-range try and then Facey got in a crucial tackle just as Matt Bloomfield's cross was about to be turned home.
Ward was also on alert to beat away El-Abd's header to keep Town on level terms at the break before the visitors almost went ahead straight after the restart though Morias, who screwed wide from an acute angle having showed great strength and pace to shrug off the defender.
Cobblers fell behind five minutes into the second-half though when Mackail-Smith got away down the left side and whipped in a perfect cross for the onrushing Williams to emphatically head into the bottom corner, giving Ward no chance.
The Chairboys perked up after that goal and could easily have had a second in a strong spell of subsequent pressure as Town's attacking threat dried up.
Jason McCarthy was particularly close when heading wide while Williams had a shot blocked before the visitors coughed up a gift of an opportunity to level.
They had done little in an attacking sense since going behind but a clumsy foul on Bridge presented Taylor - a surprise taker - the chance to equaliser from the spot, however his tame penalty was at a good height for Ma-Kalambay to push away.
But Town did not have to stew on that missed opportunity for long. Within minutes, the ball broke to substitute Hoskins in the box and he applied an excellent low finish into the far corner.
That evened things up and made for an exciting final eight minutes during which both teams looked to prevent a penalty shoot-out, though no clear chances were forthcoming and that meant spot-kicks.
Bowditch, Waters, Taylor, Facey, Bridge and Sam Foley all converted in the shoot-out but Hoskins and Turnbull saw their efforts saved and El-Abd then put away the winning spot-kick to send Wycombe through.
Wycombe: Ma-Kalambay, Harriman, Jombati (Jacobson 35), McCarthy, El-Abd (c), Gape, Thompson, Bloomfield (Morris 45), Freeman, Williams (Kashket 70), Mackail-Smith
Subs not used: Allsop, Saunders, Bean, Akinfenwa
Cobblers: Ward, Facey, Taylor (c), Barnett, Turnbull, Crooks, Foley, Bowditch, Bridge, Morias (Hoskins 73), Waters
Subs not used: Coddington, Buchanan, J Williams, Roberts, Whaler
Referee: Stephen Martin
Cobblers fans: 427