Jackson was knocked out of last week's win over the Denver Broncos because of a knee injury, which has kept him out of practice all week.
The Ravens listed him as doubtful on Friday, meaning backup Tyler Huntley will likely get the start for 8-4 Baltimore.
History says the Ravens will find victory difficult to come by against Pittsburgh without their former MVP quarterback, even against a 5-7 Steelers team that is a shadow of the former AFC powerhouse it once was.
Indeed, since drafting Jackson in 2018, the Ravens are 45-16 (73.8 win percentage) in games started by Jackson and 6-10 (37.5%) when anyone else starts at quarterback.
And, though the Steelers appear unlikely to make the playoffs, the Ravens are facing Pittsburgh likely without Jackson at a time when their arch rivals are showing signs of life.
The Steelers have won three of their past four games and have not committed a turnover in that stretch. It is the Steelers' longest such streak since turnovers have been tracked in 1950.
Mike Tomlin's Steelers have the edge in recent matchups with the Ravens. They are on a four-game win streak against the Ravens with all four wins coming by five or fewer points.
Only two matchups in NFL history have seen a team beat another five straight times all by fewer than six points (Philadelphia vs. Washington – six, 1992-95 and Raiders vs. Denver – five, 1989-1991).
Past performance from the Ravens suggests Huntley will not be able to end that run. With the Bengals (8-4) breathing down their neck in the division, there is huge onus on him to throw the formbook out of the window in a tough road matchup.