The Blues chief executive insisted he’s unconcerned about Danny Cowley’s squad returning to training next week, with virtually all their summer playing overhaul still to be carried out.
That quiet has seen fans grow increasingly restless with many of their club’s rivals busier, albeit it a market which remains slightly stagnant.
Cullen pointed out June has always been a quiet month when it comes to players moving, with things beginning to accelerate when clubs return for pre-season training.
The arrival from MK Dons gave his assessment of how he feels things will pick up, but feels Pompey are currently in a phoney transfer war.
Cullen said: ‘It very rarely happens (the squad is together for the first day of training). We’ve seen that over the years.
‘You tend to get a little bit of activity at the end of May and beginning of June.
‘June then tends to be very quiet.
‘Then it starts to grow at the end of June when people come back for pre-season.
‘Players then potentially start to see they aren’t going to be popular at their existing clubs, and then start to agitate for moves.
‘They then have to make decisions because the “beauty parade” of June, speaking to clubs and what may be best for them then suddenly starts to require some more consideration as to what’s going to happen.
‘You’ve got the Euros so the Premier League then start to free up some of their players at the end of June and into July.
‘That’s the case with some top-end Championship clubs as well.
‘The season then kicks off, you get some injuries and that starts to affect the market as well.
‘It’s a long window. I know we used to have 12 months to do transfers and it does focus the mind a little bit.
‘But there’s different dynamics and different things to how it works.’
Despite the lack of action for Pompey, Cowley has made it very clear he knows exactly what he wants in terms of the player he wants to bring in.
And Cullen feels having that clear, concise thinking is valuable when considering the transfer work which lies ahead.
He added: ‘I think having the clarity over what you want is hugely important.
‘You want to bring the right characters into the building who are going to subscribe to the philosophy that’s put into place.’
A message from the Editor, Mark Waldron
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