Ian Foster is poised to leave his role as Pompey’s first-team coach.
It is understood the 40-year-old has been offered a job elsewhere and is interested in taking up the opportunity.
Foster informed Blues boss Paul Cook of developments in the aftermath of Saturday’s 1-0 defeat at Wycombe.
He subsequently did not carry out his customary duties of overseeing the reserves for Tuesday evening’s trip to Wolves under-23s.
In his absence, Academy under-18 coach Mikey Harris took the side for their 4-2 victory, which lifted them to the top of Group D in the Premier League Cup.
Foster’s willingness to consider quitting Fratton Park represents a blow to Cook, who has moulded a tight backroom set-up.
However, Pompey discussions with the highly-regarded former Coventry City development coach are continuing.
As a result, any potential departure is on hold, ensuring he officially remains at Fratton Park.
Foster, who holds a UEFA Pro Licence, linked-up with Pompey in May 2015 following Cook’s appointment as manager.
He followed Cook’s ex-Chesterfield assistant Leam Richardson in venturing to the south-coast, completing the Blues’ new-looking coaching set-up.
The former Liverpool apprentice had previously managed Dundalk and Galway during spells in Ireland, where he came across Cook’s Sligo Rovers.
He joined Coventry in 2011, where he took on responsibility for the under-21s as the professional development phase lead coach.
Following three years at the Ricoh Arena, he left by mutual consent in the summer of 2014.