Kenny Jackett challenged Pompey to win the three matches he is convinced can clinch a play-off spot.
The Blues slumped to a 3-1 defeat at Bradford last night, an outcome dictated by individual defensive errors.
It currently leaves them one point and two places adrift of Scunthorpe in the final play-off position, having played a game more.
Crucially, three fixtures are left – Charlton, Bury and Peterborough.
Jackett believes maximum-points returns are required from all in order to fulfil the Blues’ play-off aspirations.
And it’s a mission which kicks off on Saturday with the visit of Charlton.
We are capable of doing it, we are a capable side, definitely. We have good hungerKenny Jackett
Jackett said: ‘I think we’ll need to win three out of three.
‘We have two home games and an away one with Bury.
‘If we can target three wins, it will take us to 72 points and the League One play-offs are generally 72 points plus.
‘That is where it is, we’ll need a maximum.
‘I felt in the last two months we have always needed to win.
‘We’ve been chasing slightly and haven’t had any cushion, it’s wins we’ve needed.
‘We haven’t won Saturday and we didn’t win last night.
‘If we don’t get three wins then somebody else will, so really we have to look at that points total and see if we can get as high as we possibly can and look where it takes us.
‘We are capable of doing it, we are a capable side, definitely. We have good hunger.
‘There was a certain naivety last night. We needed to be better and towards the end it was slightly frustrating because we lost our way.
‘It was hard for us to get the width required to break them down.
‘It’s where we have been for the majority of the season, just floating on the edge of it.
‘We have been threatening to be a good team and a consistent side who are a force in this division.
‘I think that’s within us, it’s within quite a number of players but we do need to find a little bit.’
Pompey slipped behind to a 14th-minute goal from Bantams defender Nat Knight-Percival.
It was poor defending from the Blues, while Dion Donohue had been caught out in the build-up and handed the hosts the fateful corner.
Brett Pitman levelled, only for Matt Lund to somehow slide a finish when Matt Clarke and Donohue appeared in control of a situation.
Then Charlie Wyke wrapped it up in stoppage-time after Luke McGee failed to hold a free-kick.
Jackett added: ‘If you don’t win boxes then you don’t win games.
‘We needed to be better in their box, better in our box. For all the running, the control, the legs we had, it didn’t result in enough.
‘We had double the amount of balls into their box and, for an away side, that is a good start but you need to get on the end of it. Too many times it was a Bradford head.
‘We had good control, good turnover and were generally better in midfield but it didn’t result in goals at either end.’