They remained in fine voice more than 30 minutes after the final whistle.
Yet their team had lost 3-0, missed a penalty, been reduced to 10-men and were comfortably outplayed.
But there were no boos, no jeers, just a constant rendition of ‘We’re on our way’ before eventually moved on by swathes of home stewards.
According to Iain McInnes, it wasn’t just Paul Cook and his players in awe of the level of support from 1,390 visiting faithful.
It was also victorious Stevenage’s directors who were left in admiration.
Pompey’s chairman said: ‘You run out of adjectives for our supporters, they are absolutely fantastic.
Fair play to Stevenage, they were the better team on Saturday but I’ll tell you what, they weren’t the better crowd.Iain McInnes
‘The Stevenage directors told me they’ve had all the big football clubs here – but never known fans like this.
‘I walked over there and clapped them myself, all the Stevenage fans were coming down saying they were absolutely fantastic.
‘We’d just lost a game 3-0, a match which we needed a point out of, and they weren’t going to leave until they saw Cook and the players.
‘It was a funny day. We had the great shot against the bar with an unguarded net and another which then hit the goalkeeper on the back and wide when normally it goes into the back of the net.
‘Fair play to Stevenage, they were the better team on Saturday but I’ll tell you what, they weren’t the better crowd.’
Renditions of ‘We are going up’ to the tune of Knees Up Mother Brown was also emanated by the away end during their post-match occupancy.
McInnes and his wife, Jane, at one point went over to applaud the noisy away supporters to show their appreciation.
Eventually a Tannoy address was made appealing for the fans to leave the Lamex Stadium, not that they paid much attention.
Once Cook left the dressing room solely with the intention of acknowledging the supporters, those remaining finally began to make their way towards the exits.
Although a number of stewards were also on hand to hurry them through.
Despite defeat, Pompey fans know they remain in pole position for automatic promotion, with a four-point gap between themselves and Saturday’s opponents.
Just as encouraging is five of their remaining eight fixtures are scheduled at Fratton Park.
Certainly spirits could not be dampened by watching their team outplayed by a Stevenage side who have now completed the double over Pompey.
McInnes added: ‘I went down to see them and applauded, I wanted to, they are just unbelievable.
‘We’ve all heard conversations about how fans are affecting the home performances and creating a nervousness among some of the players.
‘Opposition managers have in the past said they use the tension they have felt between the crowd and the team to their benefit, but I just don’t get it.
‘Our fans are absolutely wonderful, both at home and on our travels.
‘We will get over the line through this kind of support – and of course also need better performances than that on the pitch.’