The moment of enlightenment dawned after 19 minutes of the Broadfield Stadium encounter.
Granted, the ‘We’re On Our Way’ chant was offbeat, certainly it had never before been voiced by Pompey supporters.
Swiftly its unrecognisability was noted, nudges in the press box, querying looks exchanged, ears straining to decipher lyrics.
It was sufficiently special to prompt the occasion to be filmed by The News on a trusty iPhone at 8.04pm. Clearly this was no ordinary atmosphere.
A year today, the pulsating KR-L Stand was captured, its frontline occupants banging against the advertising hoardings, the Tricolour-flavoured flag swirling hypnotically.
Then there was that intriguing song.
While the words couldn’t be unravelled, it remained unrelentingly catchy, converting terrace neighbours with rapid contagion to ensure voluminous spread among Pompey numbers. As one they united in verse.
The match was goalless at the time, amid a bright start from Paul Cook’s men against their Crawley hosts. Certainly this was not supporters capitalising on glory.
Days earlier, defeat at home to Crewe produced a toxic finale, the fifth-placed Blues had been left a faltering 13-points adrift from leaders Doncaster.
Fans headed to the Broadfield Stadium that Tuesday evening with the realisation not merely promotion was at stake - but players maintaining a healthy relationship with the club’s increasingly-exasperated followers.
Irrespective of a goalless half-time scoreline, it had been an encouraging opening 45 minutes played out to a fresh soundtrack as those on pitch lifted their game.
On 52 minutes, Christian Burgess headed home Kal Naismith’s right-wing corner - and the Blues were firmly in control.
The 2-0 scoreline was later secured by Kyle Bennett’s 72nd minute effort, not only signifying victory but also Pompey occupying the top three for the first time in five months and 10 days.
Pompey would remain there for the rest of the season, ultimately bundling their way into top spot during the final 32 minutes of the campaign.
Yet while that result sparked the Blues into performing a magnificent sprint finish, the accompanying song was just as powerful.
The Meadow Lane changing rooms vibrated to ‘We’re On Our Way’ as the away occupants savoured promotion, the tune reprised in the Victory Lounge upon that evening’s return to Fratton Park.
The terrace chant had been adopted by the players - and a city sang as one on the final day’s 6-1 hammering of Cheltenham.
We’re On Our Way.