Washington Football Team pass-rusher Montez Sweat, who missed the past four games with a fractured jaw and was expected to return to practice Wednesday, tested positive for COVID-19, a source told ESPN's Adam Schefter.

Sweat, who is second on the team with four sacks this season, is expected to be out the next 10 days, which likely will sideline him two more games. Washington, which has won four in a row and currently owns the sixth playoff spot, has important games inside the NFC East the next two weeks, against the Dallas Cowboys and Philadelphia Eagles, respectively.

Meanwhile, Logan Thomas' season is over as Washington placed the tight end on injured reserve Wednesday as doctors continue to figure out the extent of his knee injury.

Washington announced that it had placed Sweat on the reserve/COVID-19 list but by NFL rules can't disclose whether it was because he tested positive or is an unvaccinated close contact.

This will be Thomas' second time on injured reserve this season, and by rule, he can't be designated to return again. Thomas already missed six games this season because of a hamstring injury, which landed him on injured reserve the first time.

Coach Ron Rivera on Monday said that an MRI revealed that Thomas did not tear his ACL, as was originally feared, but that there was damage to his knee.

Thomas was hurt with 10 minutes left in Sunday's 17-15 win over the Las Vegas Raiders when defensive end Yannick Ngakoue went low as Thomas pulled from the opposite side to block him. Rivera said he wishes Ngakoue had used his hands to fight off Thomas rather than go low.

Thomas was a key target for Washington, especially in the red zone, and had developed into a physical blocker. He caught a career-high 72 passes and six touchdowns last season, earning a three-year contract extension worth up to $24.05 million. In parts of six games this season, Thomas caught 18 passes, including three for scores. He leads all NFL tight ends since the start of last season with 151 yards receiving in the red zone. At 6-foot-6, 250 pounds, the former quarterback makes for a big target.

Washington should be helped this week with the expected return of tight end Ricky Seals-Jones, who missed the last three games with a hip injury. It also has rookie John Bates, who has earned praise for his blocking in particular.

ESPN's John Keim contributed to this report.