The Blues boss had identified Oli Hawkins as the solution – now the former Dagenham & Redbridge man is sidelined through injury.
Hawkins’ positional readjustment has been no knee-jerk response to the Blues’ defensive woes, it was first evaluated during Jackett scouting missions.
On occasions, he observed the striker target performing in the centre of defence for the National League outfit.
That alternative role resulted in a nine-game spell as a centre-back during the 2017-18 season, his maiden campaign at Pompey.
Following a year’s sabbatical, he has resumed such responsibilities, impressing before Tuesday night’s unfortunate injury exit.
Nonetheless, Jackett remains convinced Hawkins is an excellent choice.
He said: ‘Hopefully Oli can be the commanding centre-back we need.
‘We do have a number of centre-backs that could perhaps play off a big man slightly, we have a few like that.
‘I watched him a lot at Dagenham and saw him play centre-half, even though he is known as a centre-forward.
‘So when I put him there two years ago, I wasn't putting him there blind, I had seen him play in the National League playing at centre-back and at centre-forward.
‘What I now want to do is try to settle him down there and not have to move him too much, so he can work in training, work in games, as a right-sided centre-back.
‘It’s always handy when you can push him up front, but we don’t want to move him too many times. Settle him down into that role if possible and see how he gets on.
‘I would be nice to settle that partnership down, I would always want that, but similarly if things aren’t right you cannot keep doing the same thing and expecting different results, it doesn’t work either.’
Hawkins was forced off through injury on 59 minutes in the 4-0 Carabao Cup defeat to Southampton.
He sustained damage to the bottom of his left foot, with the length of absence still to be declared.