The winger stepping off the Blues bus meant he was certain to feature against the League Two side amid strong interest from Wigan.
Instead, the curveball was Tom Naylor partnering Paul Downing in a new-look centre-back partnership.
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Despite operating exclusively in a defensive-midfield role last season, the former Burton man was switched to the rearguard as Ross McCrorie and Ben Close occupied the engine room.
In hindsight, though, it’s a tactical decision that wasn’t a massive shock.
Among the excitement of the highly-rated McCrorie moving on a season-long loan, there was also the question how Jackett could accommodate both the Rangers man and Naylor in his XI.
Both are midfield enforcers with a penchant for winning the ball back – although a driving first-half run against Boro showed McCrorie can foray forward.
And if the 21-year-old was to line up with Naylor in Jackett’s favoured 4-2-3-1 system, it'd leave the Blues without a ball player who can act as a conduit in the middle third.
The Pompey boss chiefly prefers playing a defensive midfielder alongside someone who can make things tick.
Jackett has only used two players to screen the back four once previously.
That came in last season’s League One curtain-raiser against Luton, with Anton Walkes starting alongside Naylor in central midfield.
Neither had a natural instinct to get on the ball and dictate play, though.
As a consequence, it invited pressure on Pompey, with Walkes being replaced by Ben Close on 60 minutes as Jackett looked for more control.
The pairing of Walkes and Naylor never featured again, with the latter subsequently joined by someone with either energy or an array of passing.
Whether it was Close, Ben Thompson, Dion Donohue, Bryn Morris or Andy Cannon, they offered something different to the ex-Derby man, who provided the bite.
After such an impressive maiden season at Fratton Park, being awarded Players' Player of the Season, Naylor will again be a key man ahead of this term's renewed Championship charge.
But with McCrorie seen as a future Rangers captain, he’s been sent out on loan to play 40-45 games and enhance his development.
Judging by the Scot's eye-catching performance against Stevenage, he'll be a mainstay in Jackett’s line-up when available.
To sacrifice Naylor, however, would be a harsh punishment.
Jackett's been tinkering with his defence in pre-season – something he hasn’t done previously – which suggests he’s yet to decide upon his preferred partnership.
Summer arrival Paul Downing has started friendlies against UCD, the Hawks and played alongside Naylor at Broadhall Way.
After penning a three-year deal and with Jackett believing he’s in his peak years, it’d appear the former Blackburn man is first choice.
Centre-half’s not a role foreign to Naylor, having functioned there previously in his career.
And although Pompey are well stocked in that area, with Christian Burgess or Sean Raggett confined to the bench at Boro, it may be a position Naylor finds himself in more frequently.