The travelling faithful unveiled a new Gary Roberts song favourably comparing him to a ‘lower league Zidane’.
And the midfielder marked the occasion by providing the assist for Michael Smith which unequivocally assured Pompey of a play-off spot.
Paul Cook’s side were shorn of nine players for last night’s trip to AFC Wimbledon, such was the lengthy extent of their injury situation.
Yet the Blues still managed to emerge from a tight, direct affair with a 1-0 triumph to put themselves within two points of fifth-placed Plymouth Argyle in the League Two table.
In doing so it banished any chance of slipping out of the play-offs, an outcome which surely would have been planted in the realms of fantasy such was its unlikelihood.
The decisive moment arrived on 35 minutes when Roberts drove in a ball from the left into the path of Smith, who took several touches before firing home his fourth Pompey goal.
In the process the on-loan striker, who came into the side for hamstring-victim Marc McNulty, netted against the team he represented for 25 games two seasons ago.
During that period he scored in a 4-0 Kingsmeadow hammering of Guy Whittingham’s Pompey, hastening a change of manager one game later.
This time he combined with Roberts – the subject of a song delivered among the 911 visiting supporters – to give Cook’s men a gutsy victory and leave them five points off the top three.
Cook made three changes, two of which were enforced, to the side which defeated Wycombe Wanderers at Fratton Park on Saturday.
Matt Clarke (groin) and McNulty (hamstring) were both ruled out of action, so Adam Barton came into the centre of defence while Smith started in the lone-striker role.
Pompey’s boss also opted to give Kieron Freeman only his second start since arriving on loan in January.
He lined-up at right-back, with Ben Davies dropping to the bench in a tactical switch.
With Blues injuries biting deep, there were substitute presences for Pompey Academy midfielders Christian Oxlade-Chamberlain and Adam May.
For Oxlade-Chamberlain it was an involvement in the first team barely 24 hours after earning his first professional contract.
Yet Adam Webster, Kyle Bennett, Ryan Fulton and Conor Wilkinson were joined on the sidelines by McNulty, Conor Chaplin, Jack Whatmough, Clarke and Ben Tollitt.
When the match got under way, the hosts won the first corner of the game on eight minutes and very nearly opened the scoring.
Delivered by Callum Kennedy, the unmarked Darius Charles connected with a downward header which Paul Jones pushed out with a low dive.
Pompey won a free-kick in a dangerous position on 10 minutes when Sean Rigg’s boot connected with the face of Gareth Evans as he headed the ball.
Yet Kal Naismith’s delivery wastefully struck the wall and Wimbledon managed to comfortably clear.
At the other end, Enda Stevens gave away a free-kick 25-yards out.
Kennedy’s delivery was headed out by Smith before Danny Hollands was tripped by Andy Barcham to end the phase.
The Blues carved out their first chance on 19 minutes when Evans met Freeman’s right-wing cross.
However, his effort flew straight into the arms of keeper Kelle Roos.
There was little to separate the sides and the visitors conceded a corner when Rigg’s cross from the right was met by the head of Tom Elliott but crucially took a glance off Blues defender Christian Burgess to go behind.
Roberts received the first booking of the game when, on 24 minutes, he produced an ill-timed hack on Barcham.
He was soon followed into the book by Smith, who caught Charles late after the central defender had cleared his lines.
On 31 minutes, Elliott received a yellow card following an aerial challenge which caught Hollands late.
The deadlock was broken in the 35th minute, albeit amid controversial circumstances in Wimbledon’s eyes.
Rigg took a tumble under a Pompey challenge in the build-up and Roberts delivered a superb pass into the centre towards Smith.
The striker took several touches before managing to squeeze a shot through a defender and the keeper into the far corner to give the visitors the lead.
Moments later Smith had the ball in the net for a second time, only for the referee to rule the striker had delivered a nudge in the back on Paul Robinson during the move.
Pompey took their lead into the break, yet when both sides appeared for the second-half each had made a substitution.
Brian Murphy came on for Jones to make his first appearance since January, while for the hosts Jake Reeves replaced Rigg in midfield.
On 48 minutes, Barcham flashed a right-foot shot over the bar from a tight angle as the Wombles started brightly.
Robinson’s challenge on Naismith down the left earned the defender a yellow card – and almost led to the Blues doubling their lead.
Roberts picked out Naismith unmarked at the far post and the Scot was able to take a touch before unleashing a left-foot shot which Roos took at the second attempt at his near post.
Wimbledon were forcing a succession of corners, each proving difficult for the hosts to defend.
At the other end, on the hour mark, Barry Fuller’s push on Roberts earned the Blues a free-kick just outside the box.
However, the Pompey midfielder’s delivery was cleared.
There was a scare for the visitors when Barcham broke through.
But the former Blues man could do no more than drag his shot wide of the far post with only Murphy to beat.
Then a Pompey break saw Evans slip in Roberts down the right but his first-time left-foot effort ballooned over the bar when he should have done far, far better.
On 82 minutes, Fuller blocked Naismith’s close-range attempt on the line after Roberts had flicked the ball across.
And then moments later Roberts put another attempt wide.
But Pompey held on for a hard-working victory at Kingsmeadow – making certain of their place in the League Two play-offs.