Pompey will assess Liam Lawrence's fitness before finalising their side to take on Forest.
The influential midfielder limped out of the Brighton defeat with a hip problem last week and sat out training again yesterday. Ricardo Rocha is also struggling to overcome a hamstring injury.
Pompey were hoping to be buoyed by the loan arrival of defender Ritchie de Laet from Manchester United but faced a race to get the paperwork completed in time.
Greg Halford and Dave Kitson are suspended.
Pompey boss Steve Cotterill said: 'Over the Christmas period we've deserved to win two and get a draw.
'The Watford game was the only one we deserved to lose. They had more legs than us.
'Last week's game against Brighton typified where the lads are at the moment.
'In our circumstances it happens that they can get frustrated. But we will go to Forest and give them a tough game.
'They are playing well, have a good manager and are on a good run of form.
'But we have players who have played there before and will be ready for the test.'
Forest have no fresh injury doubts ahead of tomorrow's fixture.
Ex-Southampton striker Dexter Blackstock is out for a year with a cruciate knee ligament injury.
In addition, Kelvin Wilson is not ready to start following a back problem, although he could be on the bench.
However, boss Billy Davies could make two changes to the side who beat Preston 2-1 in the FA Cup.
Cup-tied Marcus Tudgay is back and could replace David McGoldrick in attack.
Nathan Tyson could also come in for Chris Cohen on the left-hand side of midfield.
Forest striker Robert Earnshaw said: 'We are on a good run generally and, at home, we are on a great run. We just want to keep that going.
'But we have to stay focused to do that. It does not matter who you are playing.
'We have to put the pressure on other teams by picking up points, by continuing to win games.
'It is huge for us, this home run. Our home form has been the biggest thing for us. It is why we are where we are. It is the reason for our progression.
'The fans help, that is a big factor.
'The crowd and the stadium are a big help.'