Three further Hamilton Academical first-team players will self-isolate for 10 days after returning positive Covid-19 tests.
Defender Lee Hodson has already been doing so after his house-mate - St Mirren's Jak Alnwick - tested positive at the start of last week.
Training has been suspended for the day while the FOY Stadium is deep cleaned.
"We will return to normal business tomorrow with further tests planned," said the Scottish Premiership club.
After Hodson's exposure to the illness, Hamilton head coach Brian Rice said clubs should expect more disruption but that he hoped it was "an isolated case" after the rest of his players tested negative.
Hamilton beat Livingston on Saturday and will now be without Hodson and three further, unnamed first-team players for the visit to Kilmarnock this weekend.
Livingston, meanwhile, have confirmed that they had no positive tests in their latest round of screenings at the start of this week.
Do players need further testing if team-mates or backroom team return a positive result? No.
Clubs have to test once per week, within 168 of any game kicking off.
Some are opting to do so twice but there is no obligation for further testing, even if there are positive results.
How do NHS Test and Protect ascertain if close contact becomes an issue? The same general rules apply to footballing staff that general public must follow, but when close contact is allowed on training field, GPS data is used.
If a person spends more than 15 minutes in close proximity with someone else, that is deemed close contact.
The person in close contact, and their household, must self isolate for 14 days.
Uefa state games can be played as long as clubs have 13 players.
Is this adopted by the SPFL? Yes, but clubs can apply for games to be postponed if they feel they are being unfairly disadvantaged.
These cases would be decided on a case-by-case basis by SPFL after consultation with the Joint Response Group and the Scottish Government.