The home-grown product has found himself employed in an unfamiliar role as Ross McCrorie’s unlikely deputy.
Despite being a left-back, Haunstrup has switched flanks for the last match-and-a-half – with impressive results.
Following two assists after entering as a substitute in the 4-1 win over Southend, he netted a maiden goal in Pompey's FA Cup victory at Harrogate Town.
Certainly the 23-year-old’s recent displays have warranted remaining at right-back.
And Jackett indicates Haunstrup may well stay there in the injury absence of McCrorie, while James Bolton and Anton Walkes are out of favour.
Pompey's boss said: ‘I don't think in terms of our creativity of full-back we have been quite good enough this season.
‘That is not necessarily picking out any individual, but, against a Southend team playing a back five, I did think there were a lot of spaces for our full-backs.
‘Brandon can drive with the ball – and he did that again on Tuesday.
‘In that particular match he did enough to be able to keep his place at right-back and didn't disappoint anybody, particularly myself, against Harrogate.
‘That’s now two good performances from that particular position from Brandon, which just goes to show a natural full-back is a natural full-back, whichever side they play.
‘You must make sure you combine well with your wingers, make sure you get your angles right, and he got a vital goal driving inside.
‘We will see if he remains there. In terms of right-backs, we have others who can play there and the Rochdale game will be a slightly different one.
‘We’ll assess that, but there is no reason why Brandon can't build on the last two performances, he has been very good.’
Haunstrup capped his 50th Blues outing with that maiden goal, levelling the Wetherby Road encounter.
Out of contract in the summer, the Waterlooville defender has served behind Enda Stevens, Dion Donohue and Lee Brown during his first-team involvement.
Opportunities have largely been hard to come by, making just two League One starts last season, of which one was on the left-hand side of midfield.
Now his reputation is deservedly on the rise – topped off by a magical moment in front of the television cameras.
Jackett added: ‘It was a great goal from Brandon, driving inside, and he has come in at right-back and had two very effective games.
‘There was Ronan Curtis’ goal as well. Both were very, very good goals, excellent strikes.’