The Chicago Bears placed quarterback Justin Fields on the reserve/COVID-19 list Thursday, putting his ability to play in the team's season finale against the Minnesota Vikings in jeopardy.
Fields, 22, had just returned to full practice Wednesday after missing the last two games due to an ankle injury.
Bears coach Matt Nagy indicated he would start on Sunday, but under revamped COVID-19 rules, Fields will have to "test out" provided he is vaccinated. If he's unvaccinated and tested positive, he can't return for a minimum of five days.
The Bears have won their last two games with Nick Foles and Andy Dalton under center. If Fields can't play, Dalton would be the likely starter. The Bears did not name a new starter on Thursday.
Fields has started 10 games this season. The Bears are 2-8 with him at the helm.