Steve Cotterill has admitted it has been tough delivering the axe to Hermann Hreidarsson.
The veteran defender has been left out of Pompey’s past two squads.
The recent arrival of Benjani Mwaruwari and Erik Huseklepp, along with Jason Pearce’s return from suspension, has boosted numbers.
That forced Cotterill to ditch Hreidarsson for the fixtures against Reading and Bristol City.
Until then, the Iceland international had made 21 successive league appearances.
Now he can’t even get in to the squad. And Cotterill admitted it has been a difficult decision.
He said: ‘It’s hard for Hermann but you have to be straight with him and I think he appreciates that.
‘I don’t fudge it for anyone so they can’t go away and say “he told me one thing and meant something else”.
‘They don’t get that from me – they get honesty.
‘It’s very difficult for me. I’ve gone from having an easy job as regards to picking the team and now, all of a sudden, it’s a bit more of a difficult job.
‘But that’s the way it has to be. It’s what the football club deserves.’
Meanwhile, former Pompey goalkeeping coach Dave Coles has joined Abu Dhabi-based club Al Jazira.
Coles was a member of the backroom staff when the Blues lifted the FA Cup in May 2008.
However, he walked out on Pompey in the summer of 2010 to join Avram Grant and Paul Groves at West Ham but was to last just a year at Upton Park.
Elsewhere, Lincoln have signed ex-Blues midfielder Jean-Francois Christophe.
Signed by Harry Redknapp in August 2007, he never made a first-team squad and later played for Southend.