Steve Cotterill has warned Pompey they are heading for trouble if they continue to rely on loan signings to prop them up.
The Blues begged and borrowed six players to bolster their paper-thin squad this season.
On occasions, Steve Cotterill fielded five on the pitch at the same time.
But while Greg Halford and Ritchie de Laet proved to be star men, the Pompey boss harbours fears about recruiting loan players on such a large scale next season.
Recently, Sheffield United chairman Kevin McCabe admitted their ‘over reliance and use of the loan market’ was one of the reasons behind their relegation.
The Blades, who will be playing League One football next term, have spent £6.5m on loan players in just over two years. This summer Cotterill urgently needs to supplement a squad which possesses just eight contracted players for next season.
But he is wary of relying on loanees rather than permanent recruits this time around.
He said: ‘This year we have absolutely ridden our luck by having as many loan players in the team.
‘We have dodged the bullet.
‘Don’t get me wrong, there is no way we could have survived without those loan players. Absolutely no way.
‘But we have also seen the pitfalls of that and it is interesting Kevin McCabe has come out and said this.
‘I can see his point of view.
‘Loans are meant to be a top up, like Millwall did. They did well with the loan system this year. They strengthened at the right time. They had a little bit of a dip and all of a sudden boom, boom, boom, two or three loans came in,
‘They kept the players in the team on their toes and finished ninth.
‘I’m not saying you can’t have a year-long loan or two in, no problem with that.
‘But when you’ve got five in you’ve got no wriggle room whatsoever.
‘What happens if three of those get injured? Who do you replace them with then? What do you do then?
‘I suppose you look back and think “how did we get away with that?”.
‘Sheffield United never got away with it.’
Halford, de Laet, Jonathan Hogg, Carl Dickinson, David Cotterill and Ibrahima Sonko joined on loan this season.
But McCabe believes his temporary players proved costly.
He said: ‘In hindsight, it is a factor which has contributed to the demise of United.
‘The over reliance and use of the loan market has had a debilitating rather than strengthening effect on the first team.
‘It was money down the drain to bring failure.’