The Chicago Bears placed Damien Williams on the reserve/COVID-19 list Thursday.
The running back had taken over as the starter after David Montgomery suffered a knee injury.
According to a source, Williams tested positive.
If he is asymptomatic and is vaccinated, he would be able to return once he produces two negative tests 24 hours apart. If he is vaccinated and develops symptoms, he would be able to return once he produces two negative tests 24 hours apart and is asymptomatic for 48 hours.
If he is unvaccinated, he would have to quarantine for a minimum of 10 days.