METAIRIE, La. -- New Orleans Saints running back Alvin Kamara has tested positive for COVID-19, leaving his status for a potential postseason opener next weekend in question, a source told ESPN's Adam Schefter.

After mixed test results, Kamara had a positive test confirmed Friday afternoon, a source said. He has been placed on the reserve/COVID-19 list and will miss Sunday's regular-season finale at Carolina.

According to the NFL's COVID-19 protocols, a player who tests positive is not permitted to return until 10 days have passed since the specimen that tested positive was collected. Kamara is eligible to return to play next Sunday provided he remains asymptomatic, a league source told ESPN's Jeremy Fowler.

NewOrleans.Football was first to report that Kamara tested positive and missed practice Friday while awaiting the results of a follow-up test.

The Saints still have an outside chance at the NFC's No. 1 seed, which would mean a first-round bye and not playing until Jan. 16-17. In addition to a win of their own, they would also need the Chicago Bears to defeat the Green Bay Packers and the Seattle Seahawks to defeat the San Francisco 49ers.

If they don't get the bye, the Saints will open the playoffs either next Saturday or Sunday.

Losing Kamara is a big blow, since he has arguably been the Saints' MVP this year while fellow stars Drew Brees and Michael Thomas have missed time with injuries. Thomas (ankle) is expected to return from injured reserve next week, but the Saints have only had their "Big Three" in the lineup together for 10 quarters all season.

Kamara, who has been healthy for all 15 games this season, should also be a leading contender for the NFL's Offensive Player of the Year award. He leads the NFL with 21 touchdowns after becoming the first player in 91 years to run for six of them in a game last week. And he ranks third in the league with 1,688 yards from scrimmage.

Kamara was 68 yards away from his first 1,000-yard rushing season.

Backup running backs Latavius Murray, Ty Montgomery and Dwayne Washington could play larger roles in Kamara's absence.

The Saints (11-4) are also expected to be without nickel safety C.J. Gardner-Johnson on Sunday after he was placed on the reserve/COVID-19 list earlier this week. Saints general manager Mickey Loomis was also away from the team this week as a precaution due to a high-risk close contact.

The Saints also ruled out safety Marcus Williams (ankle) and tight end Josh Hill (hand) for Sunday's game. And they are still without receivers Thomas, Tre'Quan Smith (ankle) and Deonte Harris (neck), all of whom are on injured reserve.

As usual, Kamara has been a huge part of New Orleans' offense as both a runner (932 yards) and a receiver (a career-high 83 catches for 756 yards). But he has been more important than ever for a Saints offense that is averaging the most rushing yards per game (140.6) and the fewest passing yards per game (237.8) in the Brees/Sean Payton era.

The Saints are on pace to run for more yards as a team (currently 2,109) than they have since 1983. Kamara has caught 67 passes in 11 games played with Brees this year, which is more than 25% of Brees' completions. The Saints have placed a total of eight players on the reserve/COVID-19 list this season: Kamara, Gardner-Johnson, Pro Bowl left tackle Terron Armstead, receiver Emmanuel Sanders, quarterback Jameis Winston, running back Washington, offensive lineman Derrick Kelly II and cornerback Ken Crawley.