Just before noon Friday, the doors to the Ravens’ practice facility swung open. Out walked the team’s biggest mystery.

Lamar Jackson was back.

“That wasn’t in doubt,” the Ravens’ star quarterback said after Friday’s practice, his first of the week after missing two because of minor back and knee injuries. “Just resting my body. It’s a long season.”

Jackson said he would “100%” play against the Denver Broncos (5-3) on Sunday at M&T Bank Stadium. Whether the Ravens (5-3) can expect him to be 100% healthy is another matter. Uncertainty hovers over the team as it looks to rebound from a stunning 29-24 loss to the Cleveland Browns and a week of unexpected headlines.

Jackson will have wide receiver Diontae Johnson available for the first time since his midweek trade, but how much chemistry will they have after Jackson’s limited week of practice? Safety Marcus Williams will play Sunday, coach John Harbaugh said Friday, but will he start? The defensive line will have Nnamdi Madubuike and Broderick Washington ready for Denver, but who else? Will cornerback Marlon Humphrey be back? Will running back Keaton Mitchell?

Answers will arrive shortly. The Ravens already got a big one with Jackson’s return. But another loss as a heavy favorite would invite even more scrutiny. Here’s what to watch in the teams’ Week 9 matchup.

1. The Ravens’ trade for Johnson should make one of the NFL’s best offenses even more threatening in 11 personnel (one running back, one tight end and three wide receivers). Good timing, too: They may need to spread things out Sunday, whether Johnson’s ready for a small workload or a big one.

Denver has one of the NFL’s best defenses in base personnel (four defensive backs), which the Ravens usually face when they line up with multiple tight ends or fullback Patrick Ricard. The Broncos rank fourth in overall defensive success rate (the percentage of plays with positive expected points added) in base — first against the pass and third against designed runs, according to TruMedia.

In nickel (five DBs) and dime (six DBs) personnel, the Broncos still have an elite pass defense. But their run defense is more middling, allowing 4.5 yards per carry and posting an average success rate, and the Ravens’ ground game will be by far the best Denver’s seen this season. According to FTN, the Broncos have played just one offense ranked in the top 10 in rushing efficiency (the No. 9 Tampa Bay Buccaneers).

Still, offensive coordinator Todd Monken said Thursday it was too early to know how Johnson could expand their offense. “The first week is always tough, you know, getting him involved, but I’m excited [from] what I’ve seen the first two days, and we’ll see where it goes,” Monken said. “Some of that is game-planning, how we want to attack somebody, how many receivers we want in the game.”

2. Ravens wide receiver Zay Flowers called Johnson a perfect fit in the team’s offense Thursday. His reasoning was, well, self-evident.

“He moves just like us,” Flowers said. By which he meant: It’s hard to cover Johnson for long.

The Ravens’ route-running chops will be tested Sunday, however. Denver is fifth in the NFL in man coverage rate (36.7%) and leads the league in blitz rate (43%), according to TruMedia, often leaving Pro Bowl cornerback Patrick Surtain II and fellow starters Riley Moss and Ja’Quan McMillian to win their matchups without much help.

The Broncos’ aggressive approach has been more boom than bust. Opposing quarterbacks have completed just 61.9% of their attempts for 6.1 yards per attempt against man coverage, averaging a dreadful minus-0.20 EPA per attempt. Only two of Denver’s eight opponents — the Las Vegas Raiders and Los Angeles Chargers — have passed for more than 100 yards against its man-to-man looks.

“Their guys are really active; they play hard,” Monken said. “That’s one thing you see on film. They’ve done a great job of building the core personalities of the players they’ve got playing on the field. I think that’s impressive, how hard they play and schematically how they challenge you with their pressure package. We’re up for it; our guys are excited. We’ve seen that for the last four weeks. We’ve seen teams that have decided to pressure us.”

The Ravens have largely handled them. Jackson has completed 64.5% of his passes against man coverage this season for 7.7 yards per attempt, with seven touchdowns and zero interceptions. Only four quarterbacks with at least 100 attempts in 2024 have averaged more EPA per attempt against man-to-man than Jackson (0.30).

Jackson’s growth as a presnap operator has given the Ravens better answers against aggressive schemes. But the elusiveness of wide receivers Rashod Bateman, Flowers and now Johnson helps, too.

“It’s going to be a lot of separation out there,” Flowers said. “It’s going to look like seven on seven.”

3. The Ravens’ run defense had its worst game of the season in Week 7. It had its worst injury luck in Week 8. Now it could face its most important test yet in Week 9.

The Broncos, led in part by former Ravens guard Ben Powers, have ESPN’s No. 7 run block win rate. Since Week 3, they’ve ranked second in the NFL in rushing success rate, highlighted by a 225-yard game against the New Orleans Saints in Week 7. Denver’s down-to-down consistency hasn’t produced boatloads of explosive plays — it’s averaging just 4.7 yards per carry and has just two runs of at least 30 yards in that span — but it has helped keep rookie quarterback Bo Nix out of obvious passing situations. Over the past six weeks, only four third-down offenses have faced a lower average first-down distance than the Broncos (6.7 yards).

The Ravens’ run defense started the season on a historic pace, but it’s trended downward in recent weeks. In a Week 7 win over the Buccaneers, they allowed a season-high 125 rushing yards, and defensive lineman Travis Jones hurt his ankle. In Sunday’s loss to the Browns, the Ravens gave up easy running lanes in the first half, when they lost defensive linemen Michael Pierce (calf) and Brent Urban (concussion) to injuries.

With Pierce on injured reserve, Urban ruled out of Sunday’s game, and Jones and Broderick Washington (knee) limited at practice this week, the Ravens could be shorthanded Sunday. Practice squad veterans Josh Tupou and Chris Wormley and rookie C.J. Ravenell are call-up options, but none has appeared in a game this season.

“Obviously, we got some guys that are banged up,” defensive coordinator Zach Orr said Thursday. “We’ll see if they make it to the game Sunday. Obviously, those guys are very important players for us, but the guys we have behind them, I’m excited about — they’ve been getting some good work in practice. Here in Baltimore, the interior D-line is something we take seriously, and we always have a contingency plan for that.”

4. The Ravens’ struggling pass rush can take a while to get home. Nix might be patient enough to let them.

Over the past four weeks, the first-round pick has an average time to throw of 3.36 seconds, the longest in the NFL. (Jackson, at 3.29 seconds, has the third longest.) Overall, 42.5% of Nix’s attempts this season have taken three-plus seconds, a far cry from some of the quick-trigger rates of other quarterbacks the Ravens have faced this season. The Buccaneers’ Baker Mayfield, Raiders’ Gardner Minshew and Cincinnati Bengals’ Joe Burrow are all under 30%.

Somehow, Nix makes it work. He’s been sacked just 11 times, a takedown rate of 4% that ranks among the league’s best, ahead of even Jackson (4.8%). Although the Broncos’ offensive line keeps Nix well protected — Denver ranks first in ESPN’s pass block win rate — he can also run himself out of trouble, with 27 scrambles for 6.5 yards per attempt.

All of this could translate to another frustrating game for the Ravens’ pass rush. Despite ranking fifth in the NFL in sacks (24), they’re just 27th in pressure rate (29%).

“Rush and coverage have to work perfectly together for it to work,” Orr said. “You can have great coverage, but … if the quarterback has a lot of time, no matter how good your coverage is, he’s going to be able to find [players], and guys are going to be able to get open. On the flip side, if your rush gets there, your coverage has to be able to sustain — at least early on — so the rush has a chance. We’ve had good examples, great examples, of the rush and coverage working together, and when it works together, it’s beautiful. … Right now, it’s not clicking as much as we need it to be.”

5. The Ravens don’t just have to consider their injury situation as they prepare for Sunday’s game. They also have to plan for Thursday’s rematch against the Bengals.

Playing two games in a five-day span can force tough roster decisions. Left tackle Ronnie Stanley, for instance, missed just one game after Week 4 last year, and it came on a Thursday night. After suffering a minor knee injury in a Week 10 loss to the Browns, Stanley was held out of the Ravens’ Week 11 win over the Bengals before returning in Week 12.

With a banged-up defensive line, Harbaugh will have to be mindful of his load management up front this weekend. Madubuike has played 59 defensive snaps each of the past two weeks, by far his season high. Washington played a season-high 41 against Cleveland but was limited in practice Wednesday and sidelined Thursday. Jones got just 15 snaps against the Browns and practiced just once this week.

Harbaugh might also favor caution in the case of running back Keaton Mitchell, a full participant in practice this week. Given the Ravens’ short turnaround and Mitchell’s long road back from a season-ending knee surgery, they could wait until Thursday to activate Mitchell off the physically-unable-to-perform list, giving him even more time to recover before their Week 11 game against the Pittsburgh Steelers.

“You definitely have to keep both games in mind,” Harbaugh said Friday of the Ravens’ approach to roster management. “When you watch the Thursday night games, you can kind of tell what a challenge it is to have your team as ready to play as they can be. So that’s definitely part of the consideration.”