The assistant manager revelled in supporters being back inside PO4 as they roared Pompey to a 2-0 victory over Peterborough on Saturday.
Two-thousand fans were in the stands for the first time in nine months amid the coronavirus crisis.
And they were at their vociferous best to inspire the Blues to a deserved win against their promotion rivals.
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As Kenny Jackett’s right-hand man, Gallen's worked at clubs in Millwall and Wolves who have similar fan-bases.
But he is adamant that his current club’s supporters are better than the rest.
Gallen told The News: ‘We gave the fans a clap after the warm-up to acknowledge they were back.
‘Let's be honest, there can't be many sets of fans than this lot down here at Pompey. They are up there with the best.
‘If that was 2,000 then wow because it didn't feel like or didn't sound like 2,000 either.
‘People thought I was joking when I thought the crowd missing was letting our home form down but I was serious.
‘The energy and support we've had for three-and-a-half seasons has been nothing else but fantastic.
‘There can't be better supporters on a consistent basis than Pompey fans. Up and down the country, I haven't seen it.
‘On a consistent basis, this lot top them (Millwall and Wolves).’
There were some question marks over how much 2,000 supporters dotted around Fratton Park would make an impact on the players.
But they were fervid from the warm-up to the final whistle and helped Pompey step their performance up a gear after a goalless first half.
Jack Whatmough and Tom Naylor both netted in the second period to deliver the fans a perfect homecoming.
And Gallen saluted every single person who was in the stands and cheered on their side.
He added: ‘The second half was our best second-half performance of the season and you have to say well done to the manager, players and fans because all three were fantastic.
‘It's 2,000 Pompey fans and 2,000 Pompey fans are a bit different than everyone else. That's how good they are. It was great to hear them and the boys and the fans hit off each other.
‘You got a thoroughly energetic performance from start to finish but in the second half, I thought it was outstanding in both.’
A message from the Editor, Mark Waldron
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