Only one member of staff at St Mirren Football Club has been found to have coronavirus after retesting discovered another six potential cases had involved false positive results.
The initial tests carried out by a private laboratory were re-examined by NHS experts and it has been confirmed only one member of staff has Covid-19.
St Mirren’s planned friendly at home to St Johnstone on Saturday was cancelled after the club reported the initial results on Thursday.
Scottish football authorities have told clubs to revert to twice-weekly coronavirus testing after the requirements were relaxed earlier this month.
No St Mirren players have tested positive for the virus.
Club chief executive Tony Fitzpatrick said: “We have complied robustly with the official testing and hygiene regimen to the letter, using a private testing facility in accordance with the Scottish Government and the SPFL/SFA Joint Response Group (JRG) protocols.
“Our players were tested on Monday July 20 and have returned 100% negative tests on Wednesday July 22.
“However test results for seven of the coaching staff undertaken at the same time showed they were positive for Covid-19.
“We immediately implemented strict isolation protocols and made further arrangements for the coaching staff to be retested at NHS testing facilities on Thursday.
“I’m very pleased to report that six of the subsequent coaching staff tests have now come back negative.
“The remaining member of the coaching staff has confirmed as a positive test result and continues to be in strict isolation and has not come into contact with any member of the playing or coaching staff since Saturday July 18.
“The club will continue to support and look after this staff member to ensure a full recovery.”
The Scottish Football Association (SFA) said it was notified of the initial positive test results on Thursday.
The SFA said: “We immediately contacted the Scottish Government and the office of the clinical director for Scotland to relay this information.
“In light of this and other recent events, the JRG hereby notifies Scottish Premiership clubs that with immediate effect they must revert to twice-weekly testing protocols until further notice.”
St Mirren are due to kick off their season at home to Livingston on August 1.
Hamilton, who they faced in a friendly last Saturday, said they are confident their safety protocols prevented any potential transmission.
The club said all players and backroom staff were tested on Monday and all the results were negative.
Meanwhile, the JRG has asked Rangers, Motherwell and Hibernian to clarify their Covid-19 testing protocols.
Rangers and Motherwell were forced to delay Wednesday night’s Ibrox friendly by two hours when results of tests carried out on Monday failed to arrive on time for the scheduled 6pm start.
Both squads came back negative but the JRG has raised questions after it emerged several Rangers players had played against Dundee United earlier that day.
Hibernian were also forced to cancel a training ground game against Ross County at late notice when their tests results arrived late.