Browns' Nick Chubb, Demetric Felton test positive for COVID-19, leaving only 1 RB available - USA TODAY

The Browns are suddenly extremely thin at running back and without one of their best players.

Running backs Nick Chubb and Demetric Felton tested positive for COVID-19 on Tuesday, a person familiar with the situation confirmed to the USA TODAY Network. The person spoke on condition of anonymity because they were not authorized to disclose medical information.

Two-time Pro Bowl selection Chubb and rookie sixth-round draft pick Felton will land on the reserve/COVID-19 list.

Chubb and Felton are vaccinated against the virus as are fourth-string running back John Kelly and practice-squad wide receiver Lawrence Cager, the person said.

The Browns announced Kelly and Cager were placed on COVID-19 lists Monday. They also tested positive.

Because the four aforementioned players are vaccinated, they would each need to be free of symptoms and produce two negative COVID-19 tests separated by 24 hours to be activated.

The development puts their ability to play Sunday when the Browns (5-4) visit the New England Patriots (5-4) into jeopardy.

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Right guard Wyatt Teller acknowledged the adversity the positive COVID-19 cases present the Browns while discussing on Zoom the four-year, $56.8 million contract extension he signed Tuesday.

Chubb is one of the best running backs in the NFL. In seven games this season (he missed two with a calf injury), Chubb has compiled 120 carries for 721 yards (6 average) and six touchdowns to go along with eight catches for 69 yards. In Sunday's 41-16 win over the Cincinnati Bengals, Chubb had 14 carries for 137 yards (9.8 average) and two touchdowns (1 and 70 yards).

Felton serves as a running back, receiver and return man. He has three carries for 16 yards (5.3 average), 13 catches on 14 targets for 147 yards and a touchdown, 26 punt returns for 218 yards (8.4 average) and four kickoff returns for 65 yards (16.3 average) this season.

The only running back on the Browns' active roster who hasn't tested positive for COVID-19 this week is D'Ernest Johnson, so the team will obviously need help at the position.

Former Pro Bowl running back Kareem Hunt remains on injured reserve with a calf injury and is expected to miss a few more weeks. Hunt landed on IR Oct. 19. 

When Chubb and Hunt were both sidelined with injuries Oct. 21, Johnson became the hero of a 17-14 win over the Denver Broncos on "Thursday Night Football." The No. 3 running back rushed for 146 yards and a touchdown on 22 carries (6.6 average). 

The Browns are not strangers to how COVID-19 can wreck a game. Their receiving corps was wiped out late last season on the eve of a 23-16 loss to the New York Jets. Five-time Pro Bowler Jarvis Landry, Donovan Peoples-Jones, Rashard Higgins and KhaDarel Hodge, who's no longer with the team, and linebacker Jacob Phillips were identified as high-risk close contacts of former Browns linebacker B.J. Goodson, who had tested positive for the virus. All six of the players missed the game.