But how things could have been different had Graham Potter landed his man before the Blues did.
The Brighton manager might not be too familiar with all of Pompey's players ahead of today's friendly at the Premier League side’s Lancing training ground.
Ronan Curtis, however, is someone Potter would have watched countless hours of in the past.
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Potter, of course, made his managerial name while in charge of Swedish outfit Ostersund.
Within seven years, he took them from the fourth tier to the Europa League.
His outstanding feats didn't go unnoticed and attracted attention from these parts – especially when they took on Arsenal in Europe.
And Curtis exploits in Ireland didn’t go unnoticed by Potter, either.
The 21-year-old winger was making a barnstorming impact at Derry City and first caught the eye of Potter featuring in the Europa League against Danish side FC Midtjylland.
Potter wasn't just tentative on the south London-born ace – he was highly keen on Curtis becoming part of his plans in Scandinavia.
So much so that Ostersunds agreed a fee with Derry in August 2017, which allowed the wide man to fly to Ostersund to discuss personal terms.
However, that's where the deal broke down. It's believed the wages the Swedish side offered weren't much better than Curtis was on at the Brandywell.
On top of that, he'd be moving to country where the cost of living is higher. He'd effectively been worse off.
Thanks, but no thanks. Curtis stayed put in Ireland.
He continued his fine form for the Candystripe and it was less than a year later after turning down Ostersund when Pompey's interest arose.
After a 1-0 defeat to Charlton in April 2018, which ended the Blues' play-off chances, Kenny Jackett wouldn't be drawn on speculation on Curtis during his post-match duties.
But those rumours proved correct. As Pompey ramped up their interest, who can forget then-Derry manager Kenny Shiels' war of words?
First, he categorically said Curtis wouldn't be moving to Fratton Park. Then claimed the Candystripes were a better team than Pompey. It provided some summer entertainment, at least.
Jackett would get his man, though, despite Shiels’ stance.
And the fee of around £100,000 has proved a snip.
During his two years on the south coast, Curtis has scored 26 goals in 94 appearances, as well as becoming a senior Republic of Ireland international.
His value has increased manifold, too. Curtis had a price tag of £3m slapped on him when Blackburn came knocking in January.
Although Brentford have been eyeing Curtis as a potential replacement for Said Benrahma this summer, Pompey plan to keep hold of their key man.
He’s tied down until 2023 so the Blues have no pressure or appetite to sell.
Instead, they're plotting for Curtis to again wreak havoc on League One – this time hopefully for promotion to be at the end of it.
How things might have been different had Potter managed to coax Curtis to Sweden before Fratton Park, though.