The undefeated Pittsburgh Steelers are dealing with their first case of a player testing positive for COVID-19 since the start of the regular season – tight end Vance McDonald.

Team spokesman Burt Lauten says the club was notified of the positive test on Monday morning, hours after the Steelers improved to 8-0 with a 24-19 win over the Dallas Cowboys. McDonald immediately self-quarantined and the Steelers remain in the NFL’s intensive protocol.

McDonald missed Friday’s practice with an “illness” according to the team’s injury report, but traveled to Dallas with the team and played 24 snaps total against the Cowboys, 20 on offense and four on special teams

The Steelers have notified the league and have been in contact with medical advisors to begin contact tracing. Pittsburgh announced last week that an unidentified staffer had been diagnosed with COVID-19.

The team had been COVID-19 free during the first half of the season.

BEARS: Chicago activated backup offensive tackle Jason Spriggs from the reserve/COVID-19 list on Monday.

Spriggs was one of two Bears players to test positive last week. Starting right guard Germain Ifedi was also placed on the list because of a close contact, and the Bears shut their facility and canceled practice last Thursday. Ifedi was cleared to play against Tennessee on Sunday.

The Bears also removed defensive back Michael Joseph from the COVID list on Monday, but he’s on injured reserve,

PACKERS: Green Bay activated linebacker Kamal Martin and running back Jamaal Williams from the reserve/COVID-19 list. Both sat out the Packers’ 34-17 victory over the San Francisco 49ers on Thursday night.

PANTHERS: Coach Matt Rhule says running back Christian McCaffrey is “day to day” with a shoulder injury he suffered in the closing seconds of Carolina’s 33-31 loss to the Kansas City Chiefs.

Rhule would not say if McCaffrey has already had an MRI or an X-ray, adding that he should know more about the extent of the injury on Wednesday. The Panthers host the Tampa Bay Buccaneers on Sunday.

McCaffrey missed six games with a high ankle sprain before returning on Sunday against the Chiefs and racking up 151 total yards and two touchdowns. He was injured with 1:10 left in the game when he was tackled near the sideline by Chiefs linebacker Dan Sorenson.

McCaffrey left the game for a few plays and was seen holding his shoulder on the sideline. He returned for one additional play before leaving again for good.

“Obviously, Christian’s a big part of this team,” Rhule said Monday. “I was happy to see him out there, discouraged for him that he got banged up, and we’ll see the extent of it as we move forward.”

McCaffrey was not made available for comment Monday by the team. McCaffrey played 59 of Carolina’s 83 offensive snaps against the Chiefs.

“I thought he played really well,” Rhule said. “I think the ball down the seam that he reached back for, I thought, was an elite play. I thought he had some really nice runs, obviously scored a couple touchdowns.”

BROWNS: Star running back Nick Chubb has been designated to return from injured reserve and is expected to practice after missing four games with a sprained knee.

Chubb sprained a medical collateral ligament in the first quarter of Cleveland’s Oct. 4 win at Dallas. He’s slotted to work out with his teammates Monday as the Browns (5-3) return from their bye week.

As long as he doesn’t have any setbacks, Chubb could return to the lineup this week when the Browns (5-3) host the Houston Texans (2-6). A Pro Bowler last season, Chubb rushed for 335 yards and four touchdowns in four games before injuring his knee.

When he was healthy, the Browns led the NFL in rushing. Cleveland’s offense hasn’t been the same without Chubb, a second-round pick in 2018 who gained 1,494 yards last season.

BRONCOS: Rookie tight end Albert Okwuegbunam is out for the year after tearing his right ACL in a loss at Atlanta on Sunday.

Okwuegbunam (pronounced owe-COO-ay-BOO-num) and quarterback Drew Lock had a built-in chemistry from their time together at the University of Missouri, and it showed during red zone drills at training camp when the two hooked up time after time for touchdowns. Okwuegbunam, who caught 17 TD passes from Lock in their two years together in college, cracked the Broncos game day lineup a month ago and had 11 receptions for 121 yards and a touchdown.

Okwuegbunam, a fourth-round draft pick, caught two passes for 45 yards in his NFL debut at New England last month, but he failed to haul in four other passes from Lock.