The Blues finished fourth in League One and will have to play three more games if they’re to clinch promotion.
Jackett’s men face Sunderland in their two-legged semi-final, with Charlton and Doncaster battling it out for the other place in the Wembley final on Sunday, May 26.
The boss stressed his side now must change their mindset from a league perspective to a knockout format.
And Pompey have proved they’re capable of delivering in one-off games on numerous occasions this term.
They won eight games en route to claiming the Checkatrade Trophy against Sunderland.
The Blues also reached the FA Cup fourth round, defeating Championship winners Norwich before being knocked out at QPR in a replay.
Jackett feels those experiences could prove beneficial.
He said: ‘It goes from a league format, which we got 88 points from and that’s nothing to be ashamed of.
‘Now it goes into a cup competition at the end of the season and we have 180 minutes where we have to come through it and come through it strongly – that’s the focus.
‘The nature of these games is anybody can beat anybody. If you have got to this stage then you are a good side.
‘For us, it’s important we work hard enough and concentrate on these upcoming games. It is a good opportunity and a big one.
‘You respect your opponent but you play it in stages and have to make sure everybody over the next two weeks focuses properly on what their jobs are.
‘I hope it helps, we have had good cup runs so I do hope that helps us.
‘We look forward to the play-offs and see it as a big opportunity.
‘Whoever you play, you’re going to have to win some big games and some pressure games.
‘You’re going to have to beat some good teams. It’s about one of the four teams going up now and we want to be that team.’
Pompey’s semi-final with Sunderland means the teams will play each other five times this season.
The Blues triumphed 3-1 at Fratton Park in December and on penalties in the Checktrade Trophy final, while the Stadium of Light showdown ended a 1-1 draw on April 27.
Jackett is relishing the renewal of the rivalry.
He added: ‘We know about Sunderland and them about us.
‘They’re two big games, two big atmospheres over the next two weeks and that’s what you’re in it for.’