Kenny Jackett has backed Christian Burgess to rediscover his Pompey form.
The crowd favourite was a pivotal figure in the side which claimed the League Two title last season.
However, the performances of the Blues defence have come under increasing scrutiny following 15 matches without a clean sheet.
Jackett believes Burgess’ own displays have dipped since Christmas, coinciding with the team’s slump.
Yet he remains an admirer of the 26-year-old, who was handed a two-year Pompey extension in November.
And the boss is convinced the central defender will recapture his best form.
Christian’s a terrific professional and somebody I have a lot of time forKenny Jackett
Jackett said: ‘Christian has been similar to the team.
‘In the first half (against Gillingham) we were pretty dominant, in the second half we fell away a little bit – and that was Christian on Saturday.
‘He has been an excellent player until Christmas, doing very well. Although defensively it hasn’t just been Christian, we haven’t done well enough this season.
‘His confidence is good. I always ask of the players to be honest in how they have done – and have an honest assessment of what they need to do going forward.
‘They must make sure they are resilient enough to pick themselves up and face any criticism that’s coming because that is part of professional sport.
‘If you see it that way, you must prove people wrong or bounce back. It’s how you come through and it’s how you react. It’s how you get on to the next one.
‘Christian has been a good player for Portsmouth and yes there have been one or two mistakes in an overall situation where the side have been up and down.
‘But overall he has been a good player for me personally and a good player for Portsmouth.
‘Christian’s a terrific professional and somebody I have a lot of time for. I know 100 per cent he will go on and prove himself again.’
Burgess has made 123 appearances and scored six times since arriving in June 2015, establishing himself as a first-choice centre-half under both Paul Cook and Jackett.
Now Jack Whatmough has returned to fitness to provide strong competition for Burgess and Matt Clarke.
Although the trio can all operate in the 3-5-2 system currently weighed up.
Jackett added: ‘At times there hasn’t been enough cover and protection in front of Christian.
‘We cannot be offering these things as excuses, you have to be able to do the job.
‘While we would definitely like more options and more senior players around us at this particular period, I don’t feel we have a group without talent.
‘There are enough defenders to get that department right and build on it and give us a sound foundation.
‘Christian can come through that and get back to his best form, I do believe that.’