Yet, significantly, the capture from Burton represents Pompey’s biggest outlay on a player since Erik Huseklepp.
It was August 2011 when the Norwegian international arrived from Bari in a £1.5m deal.
Under new ownership with CSI at the helm, manager Steve Cotterill embarked on a summer spending spree.
Also arriving at Fratton Park ahead of the 2011-12 campaign were Jason Pearce (£300,000), Luke Varney (£750,000), Greg Halford (£1m) and Marko Futacs (undisclosed).
It was Huseklepp, however, who was the marquee signing of that summer.
During the subsequent seven years and 11 months, Pompey have paid money for 17 different players.
And, with a figure approaching £1m, Harness is the most costly.
What’s more, he surpasses the previous highest also set this summer – £450,000 for Ellis Harrison four weeks earlier.
Still, with money to spend following Matt Clarke’s sale, bolstered by a sell-on clause for Conor Chaplin, owners Tornante have now entered the transfer market.
There has been no disputing Fratton Park coffers possess the ability to squad strengthen ahead of the 2019-20 campaign.
And Friday’s recruitment of Harness emphatically demonstrates the owners are prepared for involvement in transfer fees.
Some will argue it has taken too long for Kenny Jackett to spend, that the Blues have become too reliant on recruiting free transfers.
Nonetheless, in almost eight years, no Pompey regime has spent as much on a single player.
Of course, there have been many years of financial restrictions during the period since Huseklepp arrived at Fratton Park.
Administration, potential liquidation, followed by crucial stabilisation provided by fan ownership.
Blues managers Michael Appleton, Guy Whittingham, Richie Barker and Andy Awford were all deprived of a transfer kitty.
From the point of Paul Cook’s arrival in the summer of 2015, he was allowed to spend fees on Gary Roberts, Kal Naismith, Christian Burgess, Matt Clarke, Michael Smith, Curtis Main, Jamal Lowe and Nicke Kabamba.
Similarly, Jackett, appointed by Tornante in June 2017, has splashed the cash on 10 players, at varying sums.
And his latest, Harness, represents Pompey’s biggest transfer since Championship existence when buoyed by parachute payments.