The Waterlooville lad has spent the majority of his senior career on the periphery of things at Fratton Park, after graduating through the Blues’ academy in 2015.
Haunstrup turned 23 last month but only made his 50th appearance in the FA Cup win at Harrogate Town.
The former Crookhorn College pupil was firstly behind Enda Stevens in the left-back pecking order and now finds Lee Brown ahead of him.
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Ross McCrorie’s hamstring injury means Haunstrup has featured on the right-hand side of defence in Pompey’s past two games.
He's delivered two eye-catching performances, registering two assists when coming off the bench in the 4-1 victory over Southend, before bagging his first goal for his boyhood club in the 2-1 defeat of Harrogate.
Now Haunstrup is hoping for a sustained run in Kenny Jackett’s starting line-up, having made seven successive starts earlier in the season before being dropped when Brown returned from an Achilles injury.
And the cultured left-footer knows he’s capable of delivering the goods.
Haunstrup said: ‘I didn’t know it was my 50th appearance.
‘It’s been a long time. I’m 23 now and I wished I’d have done it quicker, but it’s about looking up now.
‘It is frustrating because I think that I am good enough and I know that I’m good enough.
‘Hopefully, I can start showing people that. It is frustrating but that’s football unfortunately.
‘It’s up to the manager to pick the team. I get paid to do this and I’ve just got to keep my head up and keep going.
‘I want to progress my career, play games and do what I've been doing in the past few appearances I've made which is making assists and scoring goals.
‘The only way to do that is by playing games.’
Haunstrup enjoyed his breakthrough season during Jackett’s maiden campaign as boss during the 2017-18 campaign.
He played 20 times, with 16 of those in League One, and was rewarded with a new two-year deal.
The former academy skipper has mainly had settle for a bit-part role at PO4 since, though, and his contract expires at the end of this term.
But with any talks of fresh terms on hold at Fratton Park, Haunstrup admits he has to get his head down and see what happens.
He added: ‘It’s always in the back of my head, what I’m going to do whether I’m out of contract or still under contract.
‘It’s just about getting on with things.’