Pompey are not expecting to unveil their new manager until after the League One and League Two play-off semi-finals.
The News understands the Blues’ board are comfortable with waiting to ensure they secure the best person to lead them out of the division.
And that means no appointment for at least a week as the respective play-off schedules are played out.
A five-man shortlist, which includes Paul Cook and Martin Allen, has been drawn up by the Blues.
Chief executive Mark Catlin and chairman Iain McInnes are now working through the candidates and have met several.
However, the timeframe of Cook’s availability hinges on Chesterfield’s play-off progress.
The Spireites will play Preston North End on Thursday, May 7 in the first leg of their semi-final – the second leg taking place on Sunday, May 10.
Another to have shown interest in the job is Phil Brown, whose Southend side face Stevenage for their first leg on Sunday, May 10.
The concluding leg will be held on Thursday, May 14.
Brown had announced he would be signing a three-year deal to remain at Roots Hall, yet that has still to occur.
Like Barnet’s Allen, at present he is scheduled to be a free agent at the season’s end.
Former Gillingham boss Allen, who has already held talks with the Blues, last month led the Bees back into the Football League.
However, it is understood Chris Wilder is not under consideration, despite Twitter claims.
The Northampton boss previously made the final three for the Pompey job when the hunt was on to replace Guy Whittingham.
He has since joined the Cobblers and taken them into 12th spot in League Two.