Rookie Lamar Jackson missed practice Thursday because of an illness, adding greater uncertainty to the Ravens’ quarterback situation three days from a crucial game against the Cincinnati Bengals.

Starting quarterback Joe Flacco (right hip) missed practice for the second straight day, as expected. That left quarterback Robert Griffin III, who has not played since the preseason, to take every repetition with the Ravens’ first-team offense Thursday.

Jackson did not appear to be ailing during the media availability period in the team’s locker room, and a Ravens public relations official tweeted a picture of Jackson and tight end Hayden Hurst taking in the winter’s first snow earlier.

Offensive coordinator Marty Mornhinweg said Thursday that veterans like Flacco can play well despite not practicing during the week, but that with “some guys, it doesn’t work very well.”

“I’ve had quarterbacks, tight ends, linemen, all different positions play without practicing,” he said. “Most of the guys do it really, really well, because it’s all about preparation. So yeah, I think Joe would do very, very well without practice. Because he’s got experience, he’s a smart guy, he knows how to prepare, all of those things. ... I don’t see any reason why he wouldn’t play really well without any practice.”

Jackson’s absence is an unwanted impediment for a 21-year-old possibly entering his first career start Sunday. He said Wednesday that he felt “very prepared” but acknowledged that he didn’t know yet how he could develop chemistry with the team’s starting receivers.

It would be a similar challenge for Griffin. He last played in Week 17 of the 2016 season, when he went 29-for-40 for 232 yards passing, two touchdowns and an interception in a Cleveland Browns loss. He signed with the Ravens in April and was considered to be on their roster bubble before making the team’s season-opening 53-man roster.

Ravens shift focus from Green to Boyd: Bengals wide receiver A.J. Green, a perennial thorn in the Ravens’ side, is not expected to be available to torment the Ravens again in Sunday’s showdown between the AFC North rivals because of an injured toe on his right foot.

But that news has been overshadowed by the presence of fellow wideout Tyler Boyd, who has enjoyed success in his last two games against the defense. He caught five passes for 91 yards — including a 49-yard touchdown that eliminated the Ravens from playoff contention — in last year’s regular-season finale and then six balls for 91 yards and another score in Cincinnati’s 34-23 victory on Sept. 13.

“I know they don’t have A.J., but I think Boyd, in the past two games, we didn’t really give him much respect, and he’s definitely showed us we should,” cornerback Marlon Humphrey said Wednesday. “The time they beat us last year, he did a lot of good things. So with A.J. out, I guess it’s Boyd, [John] Ross, I know they’ve got [rookie Auden] Tate. He was a guy I watched last year and he gave ‘Bama some fits. They’ve got the guys. So we’ve definitely got to respect their guys. I think it’ll be a good matchup between our corners and their receivers.”

The 30-year-old Green is tied for 18th in the NFL in receiving yards with 687 and has caught six touchdown passes. Half of those scores occurred in that Week 2 win during which he had five receptions for 69 yards.

But Green injured his toe in the Bengals’ 37-34 win against the Tampa Bay Buccaneers on Oct. 28. Without the seven-time Pro Bowl selection, the offense mustered only 174 passing yards and 284 total yards in a 51-14 shellacking by the New Orleans Saints on Sunday.

“Everybody has to do their job within the scope and the flow of the offense,” Cincinnati coach Marvin Lewis said during a conference call with Baltimore media. “[Quarterback] Andy [Dalton] is going to let the things play out, and these guys have to beat people to the spot and execute the play call. Whether it’s blocking or route-running or whatever it is, they have to do their job. When you lose a great player or have to play without a great player — we’ve all had to — everybody has to raise their level of play.”

Green did not practice Wednesday, and multiple reports have suggested that he will sit out Sunday’s game against the Ravens. But defensive coordinator Don “Wink” Martindale, who called Green “one of the best,” isn’t buying those reports.

“I don’t know necessarily that A.J. Green is not going to play in this game,” he said Thursday. “I know everybody thinks he’s not going to play in this game, but I have not heard it. So we’re preparing like A.J. Green is going to be there.”

Hurst hopes to avoid surgery:James Hurst did not practice for the second consecutive day Thursday and has sat out the Ravens’ past three games, all losses. But the starting right tackle ruled out undergoing surgery to fix whatever is ailing his back.

“Not right now, no,” the 6-foot-5, 310-pound Hurst said when asked Thursday morning if surgery is an option. “That’s not what we’re thinking. It’s not a surgery thing. So that’s obviously exciting. That was one of the first questions my wife probably asked me. But it’s not that. I’ve seen a lot of progress in what we’re doing. So we’re just going to continue along that path.”

Hurst said he did not have a timetable for his return to practice or a game.

“Just as soon as I’m healthy,” he said. “We’re working to get back. I’m working every day and getting better every single day. I’m really hopeful about the progress that I’ve made and just following the program and trusting all the people we’ve got working on it.”

Hurst, 27, started the first six games before his back flared up the day before the team’s 24-23 loss to the New Orleans Saints on Oct. 21. Since then, rookie Orlando Brown Jr. has made three straight starts at right tackle, and Hurst offered praise for the third-round draft pick’s play.

“He’s done great,” he said. “I’m really proud of him. I knew he would. He’s a very talented guy and has been blessed with a lot of physical traits that anyone would want. He’s been working hard for this opportunity, and he’s definitely taken advantage.”

In addition to Hurst, quarterbacksFlacco (right hip) andJackson(illness) and defensive back Anthony Levine Sr. (ankle) did not take part in Thursday’s practice.Griffinwas the only quarterback on the field inside the team’s indoor training facility in Owings Mills.

Strong safetyTony Jefferson (thigh) returned after sitting out Wednesday’s session and practiced on a limited basis. He was joined by left tackleRonnie Stanley (left ankle) and outside linebackerTim Williams (right ankle), who were limited for the second consecutive day.

Slot cornerbackTavon Young (ankle) practiced fully for the second straight day.

Extra points: The Ravens need a win Sunday to keep their hopes alive for a berth in the AFC playoffs. But outside linebacker Terrell Suggs dismissed the notion of revenge against Cincinnati.“We were supposed to handle their [stuff] in the first game. We didn’t do that,” he said. “No, we don’t owe anybody one. We owe ourselves one. We handle our business. We can’t be worried about anything. This is football. Games are won and lost in this league. Things happen. We owe ourselves one. I’ll say that.” … CornerbackJaylen Hill participated in Thursday’s session shortly after the Ravens announced that he was cleared to practice and had been removed from the physically-unable-to-perform list. Hill, an undrafted rookie in 2017 who made the team’s active roster, played in six games before suffering a torn ACL and MCL in his right knee. The Ravens will have three weeks to add him to the active roster or keep him on the sideline for the remainder of the season.

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