Joe Gallen hailed Pompey’s ‘brave’ defensive selections which underpinned victory at QPR.
With the Blues still reeling from the 3-3 draw against nine-man Coventry, Jackett opted for a reshuffle among his back four for last night’s Carabao Cup trip to Loftus Road.
Surprisingly, he elected to name Christian Burgess at right-back, while Tom Naylor was selected to start at centre-half for the first time in a competitive Blues match.
The third change was straightforward, Brandon Haunstrup replacing the injured Lee Brown, sidelined with an Achilles injury.
Inevitably, Jackett’s choice of right-back and the introduction of a new centre-half drew much criticism from Pompey followers before kick-off.
Yet Gallen believes Jackett has been vindicated after a 2-0 success.
The Blues’ assistant boss said: ‘We are trying to get as solid as we can at the back - and it’s brave for the manager to pick the back four that he did.
‘Let’s be honest, you look at that team selection and you would have been very surprised, especially wondering where Christian is going to play.
‘It was very brave, but I do think in terms of a back four it was the most solid we have looked this season.
‘We were good enough on the ball as well, I thought their distribution was good, but ultimately we are looking for clean sheets and we are looking for good defenders.
‘Putting Christian there, we all know he is a centre-back, I don’t think he has played right-back before, and I thought he played very well, I really did.
‘The whole team has to defend, but overall it is the most solid from start to finish that we have looked.
‘If it doesn't go well then you are opening yourself up, but it has come off and I think he has made a very good decision.’
In the case of Naylor, he featured at centre-back in the pre-season match at Stevenage and a behind-closed-doors friendly at Brighton.
And for Gallen, that selection was not quite as much as a shock.
He added: ‘Tom doesn't surprise us, he has played a bit there in pre-season and has played there for Burton.
‘Of course he hasn’t played there for us in a competitive match before last night, but he is a very consistent, unsung hero.
‘He plays midfield for us in a defensive way and looked like he had been playing there all his life.’