Richie Barker admits Ben Chorley may have to wait for his Pompey chance.
The former Stevenage centre-back, who signed for the Blues last week, is now available to make his debut after completing a three-match suspension.
But the much-improved form of central-defensive pair Joe Devera and Sonny Bradley has left Barker with a difficult selection decision ahead of tonight’s League Two trip to Wycombe Wanderers.
And while he is keen to get Chorley in the team at the earliest opportunity, the Blues boss knows the decision has been made that much more difficult in recent weeks.
‘It’s a much tougher defensive partnership to break up than it was a month ago, that’s for certain,’ said Barker.
‘There has been a big improvement as a unit, so it won’t be an easy thing to do.
‘We’ve brought Ben in to play, not just as cover, but he is the same as everyone else.
‘If somebody has got the shirt and they are doing the right job then he will have to work hard to get into the team and people need to work hard to keep him out of it.’
Devera has taken time to win the fans over after arriving from Swindon but has turned in a series of consistent displays in recent weeks.
Barker said: ‘Joe wasn’t getting massive plaudits four or five weeks ago, which was maybe a little unfair.
‘But he was part of a back four that was conceding goals so there were issues.
‘He has bought into what we’re doing. He listens when we do the work and has gained confidence – I think that is a big part.’
While Bradley has impressed at times this term, he has also struggled for consistency on occasions.
However, Barker believes the team has tightened up as a unit, rather than the team’s improved defensive resilience being entirely down to the duo.
He added: ‘I don’t think I can say it is one single thing.
‘I think the whole team’s shape has been a big part of it.
‘The closing down from the front, the reaction to losing the ball, and the defensive work we’ve done as a unit and with individuals has all added together.
‘I would say them (Bradley and Devera) playing too far apart was just one of the issues they had before.
‘But it wasn’t all down to them. I looked at all sorts of things and they weren’t getting a great deal of protection from in front of them.
‘They were getting dragged around, balls were going into the striker’s feet, crosses were coming in too easily and we weren’t winning the ball back high up the pitch.
‘I think that’s changed.’
Barker added he is happier with the increased competition for places in his squad.
He said: ‘I think there is competition everywhere now.
‘People are looking over their shoulder a bit more.
‘Looking over to the bench and seeing someone who can play in your position is not the worst thing in the world.’