Ever the pragmatist, Pompey’s boss declined to rubberneck at David Coote’s car-crash performance.
Even the eternally-cheerful Joe Gallen had combusted over the match official’s controversial Fratton Park antics.
Jackett, though, declined to become embroiled, an approach based upon natural dogmatism rather than teeth-gritted diplomacy.
‘I always accept the referee’s decision after the game and always look at my own team,’ he said afterwards.
‘If you are asking my opinion on certain incidents, I did appeal for the penalty at the time and haven’t looked at it again because there is no point. He didn’t give it and that’s it.
‘You have to accept the referee didn’t give it and you move on.’
For the Fratton faithful, there was no such desire to drain emotion in favour of applying reasoned practicality when reflecting on Coote’s display.
Not all Fratton Park stands would have been granted a clear view of Shrewsbury’s Shaun Whalley’s 32nd minute handball inside the penalty area.
Certainly those gathered in the Fratton end and adjacent stands felt strongly after Oli Hawkins had headed on Jamal Lowe’s right-wing delivery, only for the winger’s flailing left arm to intervene.
The enraged reaction from Pompey’s players was just as persuasive, at least five hurtling towards the Nottinghamshire referee upon his waving away of appeals, with Gareth Evans booked.
This was no idle claim out of desperate hope or rank sportsmanship, there was genuine conviction among supporters, players and the bench that a spot-kick should have been appointed.
Subsequent replays were just as compelling, while Pompey’s analyst department possessed a separate video feed which strengthened their own belief injustice had been served.
That moment was, of course, a mere tip of the metaphorical iceberg, Coote’s showing was consistently irritating, earning accompanying boos as he made his way off the pitch at half-time and full-time.
There was another penalty incident in the 90th minute, when the ball bounced up to strike the arm of Omar Beckles in front of the Milton end.
On that occasion appeals from Pompey’s players were strangled, almost a weary acceptance that Coote would not rule a spot-kick in their favour.
Yet for all the match officials’ undoubted inadequacy, it should not be allowed to distract from ongoing weaknesses so glaring within Pompey’s performance in a 1-0 defeat.
The Blues were particularly sloppy in the first half, several players worryingly below par, while once again the injury-ravaged midfield area is an overriding concern.
In fairness, taking into account three excellent Craig MacGillivray saves, substitute Pitman striking the bar and those penalty decisions, a point would have been justified.
However, the outcome is a winless 2018 stretching into another match as the play-off push so strong at the turn of the year is spluttering rather than driving forward with growing conviction.
How Jackett needs to bolster his squad ahead of Wednesday evening’s transfer deadline, primarily an experienced and physical central midfielder to counter the twin losses of Danny Rose and Stuart O’Keefe.
The Blues have not won since the match in which Rose sustained his broken leg, with three different replacements since employed.
It is clearly no coincidence, not that Jackett needs educating – he continues seeking personnel in that area of the pitch.
On Saturday, Adam May was recalled to the role, replacing the experiment of Dion Donohue in that heartbreaking defeat at Rotherham the previous week.
Unfortunately the teenager received a second yellow card in stoppage time, robbing the Blues of yet another midfielder for the occasion of Doncaster’s visit next weekend.
Yet pre-match, the inclusion of May wasn’t the biggest talking point – that was reserved for the omission of top-scorer Brett Pitman.
The 14-goal striker has been out-of-sorts of late, not scoring in open play in League One since November 18, while regularly being substituted, much to his obvious annoyance.
It was a massive call for Jackett to drop his skipper and potentially biggest attacking threat for the clash with promotion-hunting Shrewsbury.
Instead he recalled Hawkins as the lone striker, with Kal Naismith operating behind in the number 10 role he flourished last season.
Pompey’s boss later explained he was exploring the ‘right combination’, with Naismith providing more pace around the towering Hawkins.
As a consequence, Pitman dropped to the bench along with Sylvain Deslandes and Matty Kennedy, with Donohue restored to left-back and May coming into midfield.
The third and final change was the return of Evans following four matches out with a hamstring problem – and he was handed the captain’s armband vacated by Pitman in the process.
Evans would impress on his comeback, supplying the deliveries which created Pompey’s best goal-scoring opportunities in addition to his usual brand of surging runs down the right.
Considering the ineffectiveness of Naismith and Lowe, he was also the best of the attacking three against the Shrews.
The decisive goal arrived on 21 minutes when Whalley’s corner from the left somehow found its way to James Bolton at the far post, and the right-back netted.
Jackett later reasoned Christian Burgess had lost his man, blotting an otherwise excellent display from the central defender.
Hawkins should have levelled on 31 minutes when Naismith’s short corner found Evans and his excellent cross was headed by the striker straight at the keeper from close range.
In the second half, substitute Pitman sent a looping header from Evans’ left-foot cross goalwards, only for MacGillivray to claw it away. Naismith’s 30-yard left-footed attempt attracted a similar outcome from the impressive keeper.
Then, on 84 minutes, substitute Connor Ronan steered a header to Pitman, whose shot deflected off a defender and struck the bar.
In stoppage time, Donohue’s cross from the right was met with a Pitman shot at the far post which flashed across goal and another wasted chance.
The fans’ exasperation was focused on Coote, however, and the cast-iron penalty which never was.