It has been 405 minutes since a Blues player last registered in first-team action.
Following the second of Oli Hawkins’ two goals against MK Dons, a calamitous own goal by Doncaster is all Jackett’s side have to show from the subsequent four matches.
The latest blank was drawn in Saturday’s 1-0 FA Cup elimination at Luton.
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Keeper Marek Stech produced a man-of-the-match performance to blunt Pompey after James Collins had struck on the stroke of half-time.
Nonetheless, it represented a fourth-successive defeat amid more concerns over the Blues’ goal-scoring prowess.
Yet Jackett retains faith in his misfiring players.
He said: ‘While the bottom line is results – and I do realise that as manager – there is a lot we are doing right.
‘If we can tweak it and keep working hard and get the breaks at the right time and make the correct decisions then things will change and hopefully we will build on the confidence.
‘There are (goal) options in this team.
‘When you are looking at Pitman, Chaplin, Hawkins, Kennedy, Lowe and Bennett, they have been mainly the players I have selected along the front line.
‘Then you add Naismith, who missed Luton with a hamstring injury, and Curtis Main is around it as well.
‘There’s a number of forward options there and we have to keep working hard to find the right combination to get us the goals.
‘It’s one of those runs which happen in football. We have to recognise that we want to be winning and are losing at the moment, but we must also keep the players’ confidence high.
‘Next time they pull a shirt on they go again – and if you do that then things can turn for you.
‘Maybe we deserved a draw but we didn’t get it.
‘The keeper being named man of the match by them does show something. Right up to when we went down to 10-men we chased it hard and it’s frustrating we couldn’t find the goal or cutting edge to keep us in the tie.’
Jackett recalled Oli Hawkins for the trip to Kenilworth Road, replacing Kyle Bennett in the side and also the number 10 role.
That left Brett Pitman operating further ahead.
When asked about Hawkins’ surprising remit in the fixture, Jackett replied: ‘Defensively we had to get round and help out our midfield, which one forward does anyway.
‘It was a different combination. I thought a lot of Oli’s play was very good and was pleased with him, but we couldn’t quite get Brett into the game too many times.
‘Finding those chances and getting right in there is really important.
‘In terms of the system, it’s two forwards, but defensively one of them has to get around the holding midfielder to make sure we are not outnumbered in midfield.’