It was always going to be a tough ask for Gudjon Thordarson's off-colour team to return from Sixfields still in the competition, with Colin Calderwood and his League Two high-fliers a world apart in terms of both squad depth and finances.
When you can bring players of the quality of Scott McGleish - who scored two late goals to give the home side a slightly flattering three-goal win - off the bench, you know that Thordarson and his team had their work cut-out.
Heavy pressure followed, although it was eventually in vain as McGleish's late double ensured his team's passage to the next round of the competition.
Both manager's opted for fairly experimental line-ups, with Thordarson handing competitive debuts to two players. Shaun Marshall started in goal for the first-time since signing for the club, whilst Chibuzor Chilaka started his first-ever senior game at right back, in the enforced absences of David Pipe and Brian O'Callaghan.
The Iceman's midfield selection should also have pleased many of his doubters on the NCM Messageboard, with the attack-minded Stacy Long lining-up on the right wing, with forgotten-man Matty Williams making his first appearence under Thordarson, just behind the front pairing of Andy White and Tyrone Berry.
The positive-looking midfield didn't take long to reap rewards, with Long netting the game's opener as early as the second minute.
Early neat football from the visitors was rewarded when a defensive header fell only as far as the midfielder, who riffled home an unstoppable volley from 25-yards.
The Magpies continued to play neat football through the midfield, though the hosts themselves proved they were no slouches - and equalised as early as the 14th minute through striker Junior Mendes.
An initial corner had appeared to be cleared, but when the ball fell back into the penalty area, former Mansfield man Mendes neatly-swivelled and curled a left-footed shot in from an extremely tight angle past the reach of Marshall.
Northampton, though, didn't need to do too much for their second goal - just a minute after their first - with the Magpies quite literally gifting their hosts the lead.
Danger had appeared scarce when Kelvin Wilson attempted a back-pass to Marshall, though the youngster's attempt fell way short of the goalkeeper, giving the teenage striker Scott Cross the easiest of first professional goals, neatly slotting past the badly-exposed Marshall.
The Magpies were now in panic-mode. The lively-looking midfield were being simply by-passed, with White having little joy in holding the ball up for his team-mates.
Defensively, too, they were all at sea. The often-reliable defensive pairing of Wilson and Julien Baudet were struggling to contain Mendes in particular, with the on-loan striker testing Marshall with an 18-yard pile-driver. The rebound was squandered by Daniel Rowson, but it was obvious to the handful of travelling supporters that Notts' good start had well and truly ended.
The Cobblers' third goal eventually came in the 20th minute, with Notts' inability to defend high-balls again in evidence. Dangerous Martin Smith's corner was whipped in and Cross was afforded a free-header that he neatly-glanced beyond Marshall.
After the lighting-quick tempo start to the game, the match inevitably slowed down a bit as the half-time interval drew closer. Though the hosts were clearly in the ascendency - with Josh Low frequently exposing Notts' lack of a natural left winger - the visitors did have a golden chance to reduce the deficit going into the interval, though White badly-scuffed a free header with the goal at his mercy.
Half Time: Northampton Town 3-1 Notts County
The second half for Notts, was a different proposition entirely. The Magpies started the half in a similar manner to the first-half, with the lively midfield trio of McMahon, Long and Williams constantly probing the home defence, though this time they were able to remain on-top of the encounter for longer than the five minutes they had been in the first half.
White produced a nimble piece of footwork to work himself an opening early in the half, but his low shot fell narrowly-wide of debutant goalkeeper Michael Poke's right-hand upright.
Almost immediately afterwards, Long's powerfully struck long-range effort was well-held by the stopper as the Magpies looked to work their way back into the game.
Notts were continuing to probe, but 10 minutes after the goal Thordarson opted to switch the formation to a 4-1-2-3 system, with Williams - impressive on his return to the first-team fold - being withdrawn in favour of hitman David McGoldrick.
Notts were looking increasingly likely to send the game into Extra-time, with the midfield pairing of McMahon and Long particularly prominent. The pair were both denied by good saves by Poke, whilst Baudet saw his header from a corner cleared off the line.
McGoldrick was also denied with a couple of long-range efforts on the back of strong runs.
Unfortunately, the Magpies were unable to force that crucial third goal and it was the hosts who were to finish the game the stronger of the two teams and give the scoreline a highly-flattering look.
Substitute McGleish ended the game as a contest in the 86th minute, superbly controlling a Lowe cross and striking a shot beyond Marshall.
The prolific striker was on-target again before the final whistle, heading home another Lowe cross on the back of a superb Northampton move with what was literally the last act of the game.
Full Time: Northampton Town 5-2 Notts County
Notts: Marshall 6; Chilaka 7, Baudet 5, Wilson 5, Ullathorne 6 (Palmer 74, 5); Edwards 7; Long 8, McMahon 8; Williams 7 (McGoldrick 67, 6); White 6, Berry 5.
Not Used: Pilkington, Friars, Hurst.
NCM Notts Man of the Match: Lewis McMahon.