The oft-fractious medium of social media unified to deliver the most compelling endorsement.
The reaction among those who know was vibrant.
Millwall and Wolves supporters linking arms while booming out a chorus of approval for Kenny Jackett.
For Michael Calvin, the deafening applause was telling.
The highly-regarded sports writer spent the 2009-10 season scrutinising Jackett’s Millwall from inside the dressing room.
The output was the acclaimed Family: Life, Death and Football, which was shortlisted in the 2011 British Sports Book Awards.
I would think if the club is trying to develop a broader development strategy he would be a perfect guy to oversee that because he understands that worldMichael Calvin
Calvin subsequently scooped the 2014 Times sports book of the year honour for The Nowhere Men, while earlier this year earned accolades for No Nonsense, the autobiography of Joey Barton.
He remains a staunch admirer of Jackett, who led the Lions to promotion through the League One play-offs during that campaign of unfettered access.
The former Welsh international midfielder then steered Wolves to the League One title in 2013-14 with a divisional points record.
Having grown up together on a Watford council estate, few possess a more meticulous insight than Calvin.
Other than followers of Millwall and Wolves, of course.
Calvin said: ‘Upon Ken’s appointment, among the fans of Millwall and Wolves there was a unanimity of pleasure. You could see the number of Millwall fans who took it upon themselves to say what a fantastic choice Pompey had made and the same thing happened with Wolves followers, a bigger club and probably greater expectations.
‘Those supporters recognise the essential professionalism of Kenny Jackett.
‘People like him. There is no fuss, no frills but an awful lot of professional expertise there and I think he is perfect for Pompey.
‘He could have gone elsewhere, over the last six months he’d received several offers but when you talk about Portsmouth there is a fantastic project to be carried out.
‘He’s the right man at the right place at the right time. He knows how to get out of League One and it also appears the club are looking for someone to impose a much broader influence on its development.
‘In essence, he is a brilliant development coach who makes players better on the training ground, which is a huge asset to any football club
‘By and large, Ken is a very calm and analytical guy. He is seen as having a certain stature, you don’t have to go into a club and spew a few sound bites to be a good manager.
‘A lot of his work will be done quietly when no-one is watching – and he is in the business of making players better.
‘Make no mistake, he’s very softly spoken, very calm, very measured but deceptively hard. If he needs to tell people their fortune he will do so.’
Jackett also oversaw Millwall’s progress to the FA Cup semi-finals in 2012-13, where they lost to Wigan.
Yet following a 39-day stint as Rotherham boss, he’d been away from management since November until replacing Paul Cook at Fratton Park.
According to Calvin, though, during his sabbatical Jackett had continued to absorb the game’s knowledge.
He added: ‘Ken’s most recent role was at Tottenham.
‘With guys of that stature, when they are out of work their self-education continues and Spurs were very keen on him, so he went in to work on their under-18s and youth teams.
‘It was good for him. Good to go into another club like that and realise the real passion and perfection that goes with being at a big club.
‘Ken has a very good eye for talent, especially young talent, and I think players arriving from Tottenham will probably occur.
‘I have seen it happen before, Premier League clubs trust him.
‘Take, for example, Harry Kane. Ken had a fundamental role in getting him to Millwall on loan in 2011-12, along with Ryan Mason.
‘Spurs trust him with players. He is one of those guys the game has respect for. Sometimes when people work in the shadows the light goes on in people’s eyes.
‘When he was at Manchester City as a reserve-team coach, loads saw him working on the training ground and were impressed.
‘I know when he got the Wolves job one of the key factors was his ability to develop players. Until they were taken over – that was working well for him.
‘He’s not a chequebook manager. He is a training ground manager and I would think if the club is trying to develop a broader development strategy, he would be a perfect guy to oversee that because he understands that world.
‘I get the sense Portsmouth have done the hard yards in League Two. They are now looking for someone, over a realistic timeframe, to build through League One into the Championship.
‘Ken’s track record suggests that is a very, very realistic prospect.’
Having last week been away on a long-arranged holiday, Jackett is back at Fratton Park to mastermind progress.
He has inherited a squad, minus Michael Doyle and Enda Stevens, which last term won the League Two crown.
And Calvin is adamant the fit is one which can yield success.
He said: ‘I think it is a perfect fit. As an outsider, my view is Portsmouth is an infinitely bigger club than Wigan in terms of potential.
‘The thing that strikes me is it’s a passionate place and although Ken is not demonstrative in his passion and is quite an understated guy, he can respond to a passionate environment.
‘I’ve said it in the past, Portsmouth reminds me so much of Millwall, it’s a club which possesses a certain fanbase.
‘Ken will play it down but I think he is energised having been out of management – and this is the job he is perfectly suited for.’