Paul Cook has refused to turn on his Accrington line-up for last weekend’s lacklustre showing.
But he expects a leap in performance for Saturday’s visit of Barnet.
The Blues turned in a hugely-disappointing display at the Crown Ground for a 1-0 defeat.
Supporters hold their own opinion on the main culprits – yet those responsible were, in truth, many in number.
The result ended a sequence of four straight victories, suggesting it was nothing more than a blip.
Still, the Bees visit Fratton Park tomorrow as Cook’s side seek to bounce back from Accrington.
And the manager will not be drawn on pinpointing the individual failings during last weekend’s loss.
Cook said: ‘It was no different to the performance we had at home to Newport last year, it’s exactly the same.
‘We went to Accrington on the Tuesday night, were absolutely magnificent, the best you could play a game, and on the Saturday were absolutely abysmal.
‘What everyone wants me to do is blame personnel, I will never do that.
‘If I blamed personnel I would blame the lads who beat Accrington last year for the Newport performance afterwards.
‘We win together and lose together, that is the reality of football.
‘What happens in football is every club have people the fans want to get after, we are not going to change that and I certainly am not going to debate players.
‘You can analyse it but we are not going to change the result, you will always get flat performances from any team.
‘There can be a variety of reasons, but the reality is we were flat.
‘I must also highlight it was a bad game, we didn’t deserve to lose, we weren’t atrociously bad, it wasn’t a good game.’
Pompey face a Martin Allen side who sit 14th in League Two.
In contrast, the hosts are in fifth and are seeking a fourth successive Fratton Park triumph.
Cook added: ‘Look at the Morecambe and Accrington defeats, if we had drawn both of those we would be second in the league unbeaten.
‘There are margins in football.
‘If we draw, is it the end of the world? Then we go to Blackpool having not won in two – you can see the articles now.
‘By the way, we’d better score a goal at Blackpool otherwise we will all be jumping off the tower!’