Brian Murphy has returned to Pompey training following a groin injury.
But first-team coach Ian Foster does not believe the keeper is ready to be considered for match-day duty.
I am sure he will have come through unscathed, but he will need many more of those before we can get him back involvedBrian Murphy
The 32-year-old has been one of three Blues goalkeepers sidelined through injury during the past three weeks, prompting the recruitment of Aaron McCarey on loan.
Paul Jones (knee ligaments) and Michael Poke (collarbone) remain out of contention, yet Murphy made his training comeback on Tuesday.
Along with Alex Bass, he was put through his paces by goalkeeping coach Scott Bevan during a session on the pitches at their Copnor Road home.
The ex-QPR player has so far made seven appearances since joining on the eve of the season but Foster is cautious over when a first-team recall beckons.
He said: ‘Tuesday was Brian’s first training session.
‘He has done an awful lot of work with Sean (Duggan) in the gym and that was his first grass session.
‘I am sure he will have come through unscathed but he will need many more of those before we can get him back involved.
‘We had a match against Reading on the same day but that came too early for him considering at that point he had not taken part in a grass training session.
‘Instead it was good for the likes of Bassy to feature in that match and get minutes to help his development.’
While Murphy was unable to feature in the behind-closed-doors friendly against Reading’s under-21s on Tuesday, others received precious game-time.
Rommy Boco featured for the entire 90 minutes for the first time since joining the Blues last month.
Initially operating on the right of the attacking midfield three in a 4-2-3-1 system, he switched to right-back at half-time in place of Snorre Nilsen.
The 30-year-old is currently on loan at the Hawks, although will not feature in this weekend’s FA Cup trip to Aveley as Pompey do not want him to get cup-tied.
Meanwhile, Ben Close made his return following a hamstring injury and Nigel Atangana played 60 minutes having been left out of the squad against Yeovil Town last weekend.
Foster said: ‘Boco can play wide on the right or as a full-back when required and they were much-needed minutes for him.
‘He has obviously been at Havant but hey have an FA Cup game this weekend and he won’t play.
‘The plan was to get Ben (Close) 45 minutes – which we did – and we were pleased with how he did.
‘We are just waiting to hear back from the medical team to see if he has come through unscathed.
‘Ben Tollitt was meant to be involved but was ill, so unfortunately couldn’t.
‘Otherwise he would have played a big part.
‘There were also much-needed match minutes for Nigel.’