Matt Clarke admitted Pompey suffered a reality check after back-to-back defeats on the road.
And the popular defender insisted the Blues must bounce back against Bradford tomorrow and make a statement of intent.
Pompey registered two disappointing losses at Doncaster and Blackburn last week.
The defeats eradicated the momentum Kenny Jackett’s troops had picked up in successive League One victories against Gillingham and MK Dons.
Pompey battled to a 1-0 success at struggling Gills, in front of the Sky Sports cameras.
They then delivered their best performance during Jackett’s reign as boss with a comprehensive 2-0 win against the Dons at Fratton Park.
Nevertheless, the Blues’ momentum has since jettisoned following a 2-1 midweek defeat to Donny and then the 3-0 loss at Rovers.
Clarke revealed Pompey were handed a fresh dose of reality after those two losses.
The former Ipswich centre-back is adamant the Blues must reach the level of performance they displayed against MK Dons when they take on Bradford tomorrow.
Clarke said: ‘We played Gillingham and won 1-0 then beat MK Dons and we probably thought “we’ve cracked it here”.
‘Our opponents did not really have any shots on target and we did well not to concede in both.
‘However, you can soon come back down to reality and it’s not nice.
‘Hopefully, we can get back up to the level of the MK Dons performance again.
‘There are a number of factors why we didn’t get anything out of the two away defeats.
‘Maybe we weren’t as good as we can be, the opposition had a good day and a lot of the time it’s down to certain moments, both conceding and missing chances.’
Pompey will relish being back on their own patch against Bradford.
Jackett’s men have so far picked up four wins and one draw at Fratton Park in the league this campaign.
Although they face a Bradford side who are third in the table, Clarke insisted the Blues can put any doubt to bed by picking up three points against the Bantams.
He added: ‘The last thing you want is to get on a losing streak and people questioning if we’re up to it.
‘We have got to prove that and the way to do that is getting three points.’
– WILL ROONEY