The big former Blues favourite has spoken of his affinity with the club he emerged at as an exciting teenage prospect.
In the latest episode of the Pompey Talk podcast, which you can download HERE, Wallace admitted he would love to return to Fratton Park where he bagged 30 senior goals in 121 appearances.
The 26-year-old, who has two children with the daughter of Blues chief executive Mark Catlin, is settled and happy at Championship Millwall but stated he still holds a special regard for his first pro club.
Wallace said: ‘For me to be able to leave Portsmouth and for everyone to wish me well shows what a unique club it is.
‘That’s why one day I still hope to play for Portsmouth. I want to come back and play again for Portsmouth because I left on such good terms.
‘I just feel everyone is so nice from (steward) Roger when you get there to everyone else who’s so nice and welcoming. That’s why I’ve always wanted to come back and watch.
‘I’m marrying into a Portsmouth family anyway so I’m doomed and have to stay involved!’
Wallace’s desire to play for Pompey again follows on from Premier League star Matt Ritchie saying he’d like to return to his hometown club last month.
And the winger feels players forwarding those kinds of views over the Blues is no coincidence.
He added: ‘Portsmouth, more than any club I’ve ever seen, is respected within the football circuit.
‘It’s “what about that atmosphere - what about the atmosphere at Portsmouth”.
‘You see so many ex-Portsmouth players who want to go back.
‘I’m good mates with Ben Thompson who was down there and he absolutely loved it.
‘He’s Millwall through and through but I told him to go there, play some games and he’d love - and he did.
‘It’s that sort of club - you can fall in love with it. That’s why so many players go and come back or stay for such a long period.’
Wallace’s in-depth interview with the Pompey Talk podcast is out now and free to download HERE, or simply search for Pompey Talk on Apple Podcasts, Spotify or Sound Cloud.