Jack Whatmough and two unnamed senior players have so far tested positive and are now following recovery protocol.
Meanwhile, Whatmough’s room-mate at Hull, Ryan Williams, does not have coronavirus yet is self-isolating, putting him out of the Swindon match.
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In addition, should the two other cases not have shared together, that will in turn impact upon their respective room-mates.
Pompey will draw together all test results from the remaining members of their squad before pursuing possible cancellation of their Swindon fixture.
However, some are presently not local, having returned to families immediately after the Hull match rather than return to the south coast, in pre-arranged plans.
In the instance of Ronan Curtis, he is currently at the rural County Donegal home of parents Marie and Dave.
The Republic of Ireland international underwent a test this morning, with player and club waiting to learn the results.
In the meantime, Kenny Jackett’s customary pre-match media address has been put on hold until Pompey are certain the Boxing Day occasion will go ahead.
What’s more, the club have pledged to announce test results in one press statement, rather than dripping the outcomes publicly once they are immediately known.
In contrast, Swindon have no such issues with coronavirus at present and would head into the match with a clean bill of health, injuries excepted.
That throws up the possibility of a Fratton Park return for Brett Pitman, who joined the Robins on a free transfer from Pompey in the summer.
He netted a stoppage-time equaliser for John Sheridan’s men in Saturday’s 2-2 draw with Charlton.
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