Lamar Jackson and three other Ravens were placed on the Reserve/COVID-19 list Friday as Baltimore continues to deal with an outbreak that has now seen 12 players land on the list this week.
The other three players are fullback Patrick Ricard, defensive tackle Justin Madubuike and long snapper Morgan Cox.
With more positive tests every day this week, the Ravens-Steelers game has been rescheduled from Sunday to Tuesday night.
Jackson is the NFL's most high-profile player to land on the Reserve/COVID-19 list this season. The Ravens offense is built around the reigning MVP, who is now slated to miss the first game of his young NFL career.
Players who test positive for COVID-19 are required to quarantine for a minimum of 10 days as long as they test negative. Players who are deemed high-risk close contacts have to sit out for at least five days.
That means Robert Griffin III is now in line to start against the Pittsburgh Steelers and their top-ranked defense. With other key offensive pieces missing from the Ravens offense, Griffin will be operating a much different unit.
Here's the timeline of the Ravens' Reserve/COVID-19 list additions this week:
Monday: RB Mark Ingram II, RB J.K. Dobbins, DT Brandon Williams
Tuesday: LB Pernell McPhee
Wednesday: DE Calais Campbell, G/C Patrick Mekari, G/C Matt Skura
Thursday: DE Jihad Ward
Friday: QB Lamar Jackson, FB Patrick Ricard, DT Justin Madubuike, LS Morgan Cox
Third-string quarterback Trace McSorley is also on the Reserve/COVID-19 list (last Friday), meaning undrafted rookie Tyler Huntley is currently the only other quarterback on the roster (practice squad).
Ricard is an essential piece of the Ravens' run game. He and tight end Nick Boyle, who was lost to a season-ending knee injury, spearheaded Baltimore's multiple formations and were often at the point of attack.
Madubuike is the Ravens' fourth defensive lineman added to the list, joining Williams, Campbell and Ward. He has been a big part of the line the past two weeks, playing around 50 percent of the defensive snaps.
The Ravens have long snapper Nick Moore on their practice squad, who could be moved up to replace Cox. Cox hadn't missed a game since suffering a season-ending knee injury in 2014, meaning "The Wolfpack" has been together for 90 straight games.