One has emerged as a Premier League player of exciting promise and is being touted for an England honours.
The other has been thrown into the chase for a Championship play-off place, after his quality was quickly spotted by an international manager.
Yet, both Sean Longstaff and Ryan Yates were a whisker away from being a part of Pompey's bid for League One success under Kenny Jackett.
The Blues boss has reflected on how both young starlets became ones who got away this season.
Deals were lined up with Newcastle for Longstaff and Forest for Yates, before the moves hit the buffers late on.
Not that Jackett is getting too downbeat about that now, instead pointing to the success of the rough diamonds others failed to notice could be polished into gems.
Ronan Curtis and Craig MacGillivray fall into that category, and are signings who are now firmly Pompey assets.
Jackett said: 'There's Longstaff and Ryan Yates going in and scoring goals.
'You're looking at Chris Wood and Ashley Barnes playing up front for Burnley.
'I've had Chris Wood on loan and have tried for about four clubs to sign Ashley Barnes.
'That said, though, it's not hard to find the good players.
'Most scouts in the country and most managers and coaches will say they saw Longstaff.
'The one who can take most credit or reflect well on that one is Gary Bowyer, because he got him to Blackpool (on loan) for a year.
'The good players are pretty easy really. 'Harry Kane was always going to be a good player.
'If your timing works and you make enough phone calls to get one, that's fine.
'It's turning up the Ronan Curtises and Craig MacGillivrays (which is hard).
'Craig got to the end of last season and was out of contract.
'Lee Brown was out of contract and Ronan Curtis was £100,000.
'They're the ones, because many clubs could have taken those players or competed for them.
'Whereas everyone in my industry pretty much knew Longstaff was going to be a player.'
Former Republic of Ireland boss Martin O'Neill's arrival at Forest as Aitor Karanka's successor was the spanner in the work of the Yates deal, as he brought him into the first-team picture and killed a January deal.
Rafa Benitez opted to involve Longstaff on the club's pre-season tour as he argued with the club's hierarchy over transfer funds.
That kiboshed the Pompey move, before the 21-year-old made a big impact when being given a run in the side over the Christmas period.
Jackett added: 'We were close with Longstaff and Newcastle were considering it.
'They are very good people in terms of their feedback and they did genuinely consider it.
'That was because the experience at this club would've been good and the fact he couldn't quite break into their 18.
'They didn't want him to spend too long not playing without any focus.
'It will be interesting to follow his career now, though, because he's got a goal or two at Premier League.
'As with most of the better young players, you never do know until you put them in.
'He (Benitez) has put him in at the right time and he's responded well.'