And failure to get the potential move over the line is likely to scupper hopes of bringing in a new centre-forward to replace the 27-year-old.
Danny Cowley is desperate to freshen up his striking options, with Harrison and John Marquis now in their third Fratton Park season.
However, that depends on whether he can create space within his playing budget by orchestrating a departure for Harrison.
Sheffield Wednesday now appear out of the equation following this afternoon’s signing of Saido Berahino from Zulte Waregem.
That leaves Plymouth as suitors, while Bolton have now also been linked with the former Bristol Rovers man.
The News understands Harrison has held talks with Argyle over a potential switch, with Oxford United and Fleetwood having also enquired about him this summer.
The striker is out of contract at the season’s end, with a potential move to Home Park offering security for his young family, who are based in Chichester.
Yet, ominously, an agreement has not yet been reached, with time ticking towards the 11pm transfer window deadline.
Cowley is fully aware, he faces scrapping his search for Harrison’s replacement – if Harrison does not wish to depart Fratton Park.
That would leave Pompey falling short in attempts to introduce a striking addition to a pool containing Marquis, George Hirst and Gassan Ahadme.
A message from the Editor, Mark Waldron
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