Jackson's absence puts his availability in question for Sunday's game against the Los Angeles Rams, which is critical to Baltimore's fading playoff hopes. Jackson is dealing with a right ankle injury that has sidelined him for the past two games.
If Jackson is out again, Tyler Huntley would make his third start in the past seven weeks. Huntley, who missed Sunday's 41-21 loss in Cincinnati, returned to practice Thursday after being activated off the reserve/COVID-19 list.
Jackson hasn't played since injuring his ankle Dec. 21, when Baltimore lost at Cleveland 24-22. After sitting out for 17 days, Jackson practiced Wednesday but had a pronounced limp. He had trouble jogging while moving from drill to drill.
This is the first time in Jackson's four-year NFL career that he has missed consecutive games.
Asked before Thursday's practice whether Jackson needed to be at a certain percentage health-wise to play, Ravens offensive coordinator Greg Roman said: "I'm sure in his mind he's ready to play. But as coaches, it's our responsibility to make sure he's in good enough health that he can go out there and play the way we need him to play ... and make sure he can protect himself adequately. So that's definitely a process that goes on day to day."
The AFC's top seed five weeks ago, the Ravens (8-7) are now No. 8 in the conference's seven-team playoff field. Baltimore is facing an essentially must-win game against the Rams after losing four straight games. If the Ravens lose, their playoff chances dwindle to 8%, according to ESPN's Football Power Index.
Baltimore has had a revolving door at quarterback recently, starting Jackson, Huntley and Josh Johnson over the past three weeks. It's the first time in Ravens history that they started different quarterbacks in three consecutive games.
Huntley, who went undrafted out of Utah in 2020, has become a more than capable fill-in for Jackson. In his last start -- a 31-30 loss to the Green Bay Packers on Dec. 19 -- Huntley became the first Ravens player ever to record multiple touchdown passes and touchdown runs in the same game.
With how Huntley has played, it could be difficult for the Ravens to go with a limited Jackson against a Rams defense that is tied for fifth in the NFL with 42 sacks. Roman said the Rams defense is "extremely explosive up front" and Pro Bowl defensive tackle Aaron Donald is "darn near unblockable."
The Ravens are looking to avoid their first five-game losing streak in coach John Harbaugh's 14 seasons.