It is understood Steve Cotterill’s side had enquired over the availability of the Blues forward – interest which was welcomed rather than rebuffed.
With Sam Cosgrove earmarked for an early return to Birmingham following an unsuccessful loan scheduled to last the season, the Shrews had a striking vacancy.
However, they yesterday completed the signing of Saikou Janneh on loan from Bristol City for the remainder of the campaign.
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The 21-year-old, who previously had loan stints at Torquay and Newport County, will now challenge regular strike pairing Ryan Bowman and Daniel Udoh for a starting spot.
And that casts severe doubt over whether they now also require Pompey’s Harrison.
Yet Shrewsbury were viewed as possessing greater financial clout to come close to meeting his Fratton Park wages, particularly with Cosgrove’s impending exit.
Cotterill, however, has now gone for Janneh, who has made two appearances for Bristol City this term.
He joins a striking pool which features former Exeter man Bowman, who has netted nine times in 24 appearances this season.
In addition, Udoh has registered six goals in his last eight League One appearances to fire the Shrews up the table following early relegation trouble.
Their form has forced Cosgrove on the sidelines, with the player purchased by Birmingham for £2m just 12 months ago having netted just twice in 22 outings.
He is expected to return to his parent club this month, while winger Khanya Leshabela is anticipated to be going back to Leicester City after also struggling.
Meanwhile, Pompey remain keen to remove Harrison from their wage bill as they attempt to create space in their budget to recruit improved striking options.
The former Ipswich man’s time at Fratton Park has been hammered significantly by injury and he has started just one league game this season.
Meanwhile, Norwich loanee Gassan Ahadme will be returning to Norwich at the halfway point of his arranged season-long stay having failed to establish himself.
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