The Blues head to Crewe tomorrow night with potentially just three senior forwards to chose from in Ronan Curtis, Ryan Williams and Marcus Harness.
Pompey have an injury crisis in the final third of the pitch.
Michael Jacobs become the latest casualty, having been ruled out for the rest of the season with a knee injury.
A similar problem will keep Ellis Harrison sidelined for the remainder of the campaign.
To make matters worse, though, John Marquis’ return from a three-match ban following his red card at Shrewsbury could be on hold, with the striker having had two injections for an ankle problem.
Hackett-Fairchild is currently out on loan at League Two strugglers Southend, where he's scored once in 20 games.
Pompey were able to recall the ex-Charlton man when he was at National League side Bromley during the first half of the campaign.
But because Hackett-Fairchild joined a Football League club in January, that is an option the Blues can no longer take up.
Head coach Cowley said: ‘I’d like to have one or two of the boys out on loan back available to us but that’s not possible.
‘To be fair to Reeco, he is well capable of playing League One and League Two football and doing really well.
‘If he's going to go on loan for game-time, you have to make sure the loan is the level of challenge he needs.
‘I understand why they (former boss Kenny Jackett and his staff) would have done that for development reasons, but it is a shame he's not in the National League because we could then recall him.
‘He'd come back into our squad and would make a big difference to the group right now.’
Pompey also have third-year scholar Teggart on loan at Irish Premiership outfit Cliftonville.
Yet the Blues can't send for Teggart, either.
Cowley added: ‘We can't unfortunately. It is what it is.
‘Hindsight is a wonderful thing. If I had hindsight on my side, I could probably rule the world.
‘None of us do so we have to keep learning, looking at the decisions we make, analyse it and think: "Was that a good decision or not a good decision?"
‘I'm never scared of making mistakes, we're all human. What you don't want to do is keep making the same mistakes.’
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