The duo have been outstanding Fratton Park loan recruits this season – yet inevitably will return to their parent clubs at the end of the month.
Clearly their exits will create a huge hole in the Blues side, throwing up concerns whether replacements of equal calibre can be recruited in their place.
And he is convinced similar quality can be signed during what promises to be another busy summer for Pompey.
Cowley told The News: ‘Some players are impossible to replace – and that’s the challenge.
‘Equally, there is an opportunity for us to strengthen in other areas as well.
‘Like a lot of clubs in League One, we know we must use the loan market, there aren’t many that don’t have to.
‘And when a loan signing does well, the challenge is about replacing them.
‘The good news is any parent club can see that we look after their players well, we are good at developing young players.
‘Hopefully they see the pathway that Hayden and Gavin have had and gain confidence in the way we work – then are more willing to loan their players to us in the future.
‘We are in a much, much better place going into this summer than we were last summer, that’s just a fact.
‘We also know that recruitment is 80 per cent of the job and I think my track record across the levels shows we’ve been able to do that if given the freedom – and that’s what we’re really excited about.
‘We have much more freedom this summer window than last and are looking forward to trying to utilise that and making the most of it.
‘Those players were found through hard work, getting out and watching games. We have a recruitment model, a lot of work goes into identifying those players.
‘And we can do that again.’
Bazunu replaced The News/Sports Mail’s Player Of The Season Craig MacGillivray in the summer, going on to enhance his reputation as one of the finest young goalkeepers around.
As for Carter, the former Burton loanee has been magnificent in a variety of defensive roles after stepping down from the Championship, where he had made nine appearances this term.
Cowley added: ‘Let’s be honest, when we let Craig go at the end of last season there was a lot of disappointment.
‘In terms of that decision, I don’t think anyone can criticise it because Gavin has come in and done what he has done.
‘In my ideal world, for the future of this football club, somewhere along the line we will not have to rely on the loan market.
‘However, at the moment in the here and now, we need to. This is the journey we are on.’
A message from the Editor, Mark Waldron
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