gap Connah's Quay Nomads saw their superb eight-match winning streak come to an end as Porthmadog claimed a deserved victory on Deeside.
The visitors took advantage of an alarmingly lethargic display by the league leaders thanks to a first half double from Paul Roberts - either side of a Dean Thurston equaliser - to avenge their 3-1 home reverse in January.
Nomads welcomed Rob Jones and Tommy Baker back into the starting line-up, but at the expense of influential player-manager Mark McGregor and the league's leading scorer Gary O'Toole, who were only fit enough to be named as substitutes following recent strains.
Ironically, McGregor and O'Toole were both awarded with their respective Manager and Player of the Month awards by the Huws Gray Alliance a few minutes prior to seeing their team-mates initially struggle to break down a compact Porth defence.
Indeed, the opening quarter hour provided nothing in the way of goalmouth action, with both rearguards standing firm to deflect the few attacks their opponents created, and it was not until the 19th minute when the first real opportunity of note arrived.
That opportunity was taken by the visitors' dangerous striker Roberts when he found space behind the heart of the Nomads defence to meet a through ball, before picking his spot beyond the advancing Adam McGee to give Gareth Parry's side the lead.
Nomads have proved their mettle when it comes to conceding first, though, and levelled the scores with their first clear opening of the game just past the half hour mark.
Pacey winger Jamie Petrie made inroads down the right flank and his pinpoint cross was met at the near post by Thurston who plundered his sixth goal of the campaign.
Despite the deadlock now having been broken at both ends, both sides continued with their struggle to unlock tight defences - the best chances falling to the visitors, but Ben Collins was on hand to deny two dangerous crosses in quick succession, putting the ball out for corners.
It took an unexpected goalkeeping howler by McGee to supply what would ultimately prove to be the winning goal.
The former Rhos Aelwyd stopper looked to have gathered Cai Jones' innocuous left-wing cross comfortably on his goal-line, only to then drop the ball loose for two sky blue shirts to pounce - Roberts getting there first to tap over the line from a yard out.
Coming as it did a minute before half time, Porth's regaining of the lead was a severe dent in Nomads' bid to stretch their winning run to nine matches, but the home side were determined to make amends in a vastly more entertaining second period.
The visitors began to control possession in a way not seen by either side during the previous 45 minutes and lively wide men McDaid and Cai Jones both came close with efforts from distance - McGee holding on to one and another flying narrowly wide.
At the other end Nomads saw their best chance of the game go begging when Collins' cross from the left picked out Thurston at the near post, but the former AFC Liverpool frontman saw his first-time shot diverted onto the top of the crossbar by Richard Harvey's outstretched leg.
Nomads needed to solidify their foundation and the self-introduction of McGregor midway through the half went some way to doing that, whilst Sam McNutt was thrown on in place of playmaker Rob Jones in an attempt to bring some steel to attack that had given the Porth defence an easy time for the first hour.
The tactical switch brought McGregor's charges back into the game, for the most part, particularly when O'Toole entered the fray ten minutes later at the expense of Thurston.
Now the hosts looked more assured going forward, with Petrie raiding the right flank and Collins and O'Toole combining well on the opposite side.
One such Petrie charge resulted in a neat cut-back from the right byline to an unmarked McNutt, who had made a late run into the area, but the substitute's low effort was blocked by Harvey - Petrie putting the follow-up cross straight into the 'keepers arms.
Moments later, an exact replica move ended with a well-positioned Collins blazing over in a crowded area, as McGregor had pushed himself and Andy Alston forward with the clock running down.
O'Toole also sent an acrobatic volley over Harvey's goal as Nomads continued the surge, although the hitman was flagged offside.
Naturally, it was not quite a late bombardment with Porthmadog also causing one or two nervy moments for the home defence through substitute Darren Gowans, the left-winger driving narrowly over from outside the box, before centre back Gareth Owen headed high from a set piece.
With time running out, Nomads made headway in an attempt to salvage something from a thoroughly disappointing afternoon, but the dismissal of the influential Andy Alston for lashing out at a Porth defender off the ball only served to compound the home sides woes.
Alston reacted to a desperate swinging tackle by raising his arms to push his opponent to the ground and now looks likely to serve a three match suspension for his crime.
Nomads head to Llandudno on Friday evening targeting an immediate recovery from a bad day at the office.
NOMADS: Adam McGee, Ben Alston, Ben Collins, Tom Baker (Mark McGregor 58'), Andy Alston, Craig Jones, Jamie Petrie, Alan Hooley, Dean Thurston (Gary O'Toole 69), James McIntosh, Rob Jones (Sam McNutt 58').
Substitutes Not Used: Danny Pinch, Louis Mackin.
Booked: Craig Jones 64'
Sent Off: Andy Alston 90'+2