Montez Sweat, who missed the past four games with a fractured jaw, tested positive for Covid-19, a source told Adam Schefter.
Sweat, who is second on the team with four sacks this season, is expected to be out for 10 days, which will sideline him for two more games. Washington has two important games in the next two weeks, against the Dallas Cowboys and Philadelphia Eagles, both of which are currently in the playoff picture.
Washington placed the tight end on injured reserve as doctors try to figure out the extent of his knee injury.
Washington placed Sweat on the reserve/COVID-19 list, but by NFL rules can't say if it was because he tested positive or if he was unvaccinated.
Thomas will be placed on injured reserve for the second time this season and can't be designated to return. Thomas was placed on injured reserve for the first time this season because of a hamstring injury.
The coach said that the injury to Thomas' knee was not as bad as first thought.
With 10 minutes left in Sunday's 17-15 win over the Las Vegas Raiders, defensive end Thomas was hurt when he pulled from the opposite side to block the defensive end. Rivera said he wished that Ngakoue had used his hands to fight off Thomas.
Thomas was a key target for Washington and had developed into a blocker. He caught a career-high 72 passes and six touchdown passes last season, earning a three-year contract extension worth up to $24.05 million. In six games this season, Thomas caught 18 passes and scored three times. He leads all tight ends in red zone receiving since the start of last season. The former quarterback is big and strong.
Ricky Seals-Jones is expected to return this week after missing the last three games with a hip injury. It also has John Bates, who has been praised for his blocking.
John Keim is a contributor to this report.
