Gillingham 2 Portsmouth 0 '“Â Neil Allen's match reportÂ
It had to end, just disappointingly for Pompey it arrived following Sunderland.
After four months and 16 days, Kenny Jackett's men have finally tasted away defeat in the 2018-19 campaign.
A club-record 14 games in all competitions, the backbone of the league leaders' presence at League One's summit.
Yet, against Gillingham, the Blues were finally halted.
The scoreline read 2-0 to the Gills, with a goal at the end of each half inflicting that maiden defeat on Pompey's travels.
Days earlier, a 3-1 success over Sunderland represented proof of the Blues' promotion credentials at a europhic Fratton Park.
Then there was the Boxing Day trip to Priestfield. The hosts had inflicted Pompey's first loss of the campaign in October '“Â and repeated the trick in travelling terms during the corresponding fixture.
In truth, Steve Lovell's men had registered through Josh Park on the stroke of half-time entirely against the run of play.
Jackett's troops had dominated until that point, appearing comfortable and in control, albeit wasteful inside the box and ineffective from their many set-pieces.
Still, there was little fear the score could not be reversed during the second period, yet opportunities again were not taken.
Jackett had even used all his substitutions on 69 minutes, with Brett Pitman, Andre Green and David Wheeler thrown on in search for an equaliser.
When Nathan Thompson limped off with a hamstring six minutes later, the visitors had to see out the final 15 minutes with 10 men.
That proved decisive, with the Gills subsequently far too comfortable defensively, while a break-away moment through Elliott List sealed victory on 90 minutes.
Callum Reilly netted that subsequent penalty '“Â and the only unbeaten away team in the top eight tiers of English football had lost their proud record.
Jackett named his familiar starting XI, continuing to be untroubled by fatigue and injury.
Ronan Curtis had been a doubt after troubled by a tight quad, forcing him off late in the 3-1 victory over Sunderland.
But he was able to retain his spot to face a Gills side sitting in 19th place head of kick-off.
The Blues' bench was also unchanged, with Alex Bass continuing to deputise for the injured Luke McGee as substitute keeper.
Yet again there was no place for loanee Joe Mason in the match-day 18, along with Danny Rose, Dion Donohue, Louis Dennis, Brandon Haunstrup and Adam May.Â
The visitors started the match strongly and, on eight minutes, created the game's first meaningful chance.
Left-back Lee Brown galloped to the byline and pulled the ball back where is was met with fierce Gareth Evans snapshot which appeared goalbound.
However, it crashed against a defender and ricocheted for a right-sided corner, with the Blues skipper clearly aware how close he had come to netting.
Then Connor Ogilvie's poor header back was capitalised on by Jamal Lowe, who burst into the box, although edging out wide.
He was then held up by Gabriel Zakuani, who did enough to slow the move and ensure it petered out as Lowe failed to find Tom Naylor's late surge into the penalty area.
On 15 minutes, Evans' backheel sparked a wonderful Pompey move down the right which culminated in Oli Hawkins hooking a left-footed shot towards goal.
The lurking Lowe stopped in anticipation of the ball finding its way in at the far post, but instead the shot trickled agonisingly wide.
The first booking of the match was handed on 20 minutes to Mark Byrne, who cynically took down Lowe as he surged down the right flank.
Pompey were continuing to probe away and Ben Thompson had a left-footed shot from distance changed down, deflecting for yet another corner.
On 38 minutes, Curtis fouled Josh Park in a dangerous position down the right but the Blues were excellent aerially to clear the free-kick.
In Pompey's next attack, Lowe pulled the ball back from the right and, while Curtis' first-time right-footed shot was not clean, it still forced Tomas Holy into a save.
From the resulting corner delivered by Evans down the right, Hawkins saw his header cleared off the line by the flying Barry Fuller.
The deadlock was broken, though, on 44 minute, albeit very much against the run of play.
Elliott List produced a wonderful left-footed cross from the left and Parker rose to head home and give the Gills the lead.
Jackett's men had been in complete control, yet now entered half-time trailing.
There were no changes at break, with the Blues emerging strongly.Â Hawkins agonisingly failedÂ to turn home at the far post Ben Thompson's whipped in cross from the right.
At the other end, Dean Parrett's curling free-kick was missed by his team-mates yet still had to be tipped around his far post by Craig MacGillivray.
Evans should really have levelled on 54 minutes when excellent work down between Curtis and Brown saw the latter pulled the ball back only for the skipper to rifle a first-time left-footed shot over.
Then Curtis' cross from the left was headed narrowly wide by Hawkins, who had managed to get ahead of marker Zakuani.
Pompey made their first change on 59 minutes, with Brett Pitman introduced for Hawkins.
Then Jackett made a double substitution, with Andre Green and David Wheeler put on for Curtis and Lowe in the 69th minute.
The visitors were pouring forward and when Brown fired in a cross from the left, Pitman couldn't get a vital touch from close range to net.
With all substitutes utilised, when Nathan Thompson appeared to pull a hamstring on 75 minutes there was no-one to replace him, leaving Pompey with 10 men.
Still the one goal separated the sides, and when Green pulled the ball back from the left, Pitman's swivelled and drove an attempt straight at Holy.
On 90 minutes, the game was wrapped up in Gillingham's favour when List was brought down by Jack Whatmough inside the box after hitting the Blues on the counter attack.
Reilly did the rest, sending MacGillivray the wrong way, with only five minutes of time added on remaining.