The Bears on Thursday placed rookie quarterback Justin Fields on the reserve/COVID-19 list, putting his availability for Sunday's season finale against the Vikings in Minnesota in doubt.

On Dec. 15, the NFL announced that vaccinated players and staff who are asymptomatic for at least 24 hours can return as early as the day after their positive test if they meet any of the following criteria:

1) They receive two BRL PCR test results that are either negative or produce Cycle Threshold (CT) values of 35 or greater.

2) They receive one BRL PCR test result that is either negative or produces CT values of 35 or greater AND receive a negative Mesa test result from a test taken within 24 hours of the BRL PCR test.

3) They receive two negative Mesa test results, with a maximum limit of three tests taken per day.

The Bears had planned to start Fields in the season finale. He returned to practice Wednesday without limitations after missing the last two games with an ankle injury he sustained Dec. 20 in a loss to the Vikings.

The Bears moved up nine spots in the first round of last year's draft to select Fields at No. 11 overall. He has appeared in 12 games with 10 starts. The former Ohio State star has completed 58.9 percent of his passes for 1,870 yards with seven touchdowns, 10 interceptions and a 73.2 passer rating. He has also rushed for 420 yards and two TDs on 72 carries.

If Fields is unable to play Sunday, veteran Andy Dalton likely would make his second straight start. In last weekend's 29-3 drubbing of the Giants, the 11th-year pro passed for 173 yards with one TD, one interception and a 63.2 passer rating in his first start since Dec. 5 in a loss to the Cardinals.

In his first season with the Bears, Dalton has appeared in seven games with five starts, completing 61.7 percent of his passes for 1,190 yards with seven TDs, seven interceptions and a 76.8 passer rating.

Check ChicagoBears.com later for expanded coverage.