Pompey have opted against offering Aaron Jarvis a contract.
And Kenny Jackett has outlined triallists will have to offer him a marked improvement on his existing players to be given a chance with the Blues.
But the Pompey boss opted against extending the former Luton striker’s stay with his side.
The 21-year-old was released by the Hatters in the summer, following their promotion to the Championship.
Jarvis made 14 appearances at Kenilworth Road, scoring two goals, and spent the second half of last season on loan with Falkirk in the Scottish Championship.
Jackett had a good look at the former Basingstoke man but decided against extending his stay.
He said: ‘Aaron Jarvis was released at lunchtime.
‘In terms of a number nine he wasn’t quite what I was looking for.’
Jackett is not planning to take any triallists away with him on Pompey’s pre-season to Ireland.
That means he will continue his record of not using any players who are trying to earn a deal in warm-up games, since arriving at Fratton Park in 2017.
The Blues manager explained giving triallists an appearance is something he’s prepared to do, but he feels that can’t be at the detriment of blooding academy youngsters.
And Jackett explained the triallist has to be a marked upgrade on what the club already has at their disposal.
He added: ‘It’s not necessarily (a deliberate ploy not playing triallists).
‘But I do think pre-season is a good chance to put the academy boys in, which you don’t normally get through the season.
‘Okay, I’ve used the Checkatrade and the reserve games.
‘But pre-season is traditionally a time to look at younger players.
‘If there is a triallist which is that close and can make a difference that’s fine.
‘But you have to make sure that you’re not blocking up your system.
‘There were players like Haji (Mnoga) last season.
‘There’s no point in having a pathway if players like Ben Close, if you like, aren’t going to get through.
‘If you’re looking at looking at triallist who is 20 or 21, you may have a 17 or 18-year-old in the building and you have to make sure the triallist doesn’t block them.
‘In the end they have to be significantly better - that’s the bottom line.’