In dismantling the Rams in Los Angeles last Monday night, the Baltimore Ravens looked as unstoppable as ever. But with San Francisco coming to town this weekend in what some are predicting to be a Super Bowl preview, the Ravens are dealing with the one thing that can stop any team in its tracks: a big injury. Whether the absence of Matt Skura actually even slows down Baltimore remains to be seen, and the 49ers also have their own injury issues, as well. San Francisco still isn’t even sure of everyone who’ll be available come kickoff. But with numerous teams with playoff hopes dealing with injuries, depth is becoming an increasingly important factor as the calendar turns to December.

10. Eagles TE Zach Ertz, RB Jordan Howard
Status: Questionable (Ertz, hamstring; Howard, shoulder)
Level of Concern: Moderate and improving
Next Up: Following last Sunday’s dismal showing at home in a 17-9 loss to Seattle, the Eagles couldn’t have asked for a much better start to this week so far. The Cowboys lost on Thanksgiving, meaning a win in Miami this Sunday would put the Eagles in a tie for first in the NFC East. On Friday, a handful of Philadelphia players were removed from the injury report. And OT Lane Johnson (one of the players taken off the injury report) signed a four-year extension. Now comes word that Ertz returned to practice Friday, and he is expected to play, too. The only downer is Howard, who has yet to be cleared for contact and seems unlikely to play.

9. Vikings WR Adam Thielen
Status: Questionable (hamstring)
Level of Concern: Easing
Next Up: Thielen — and the Vikings — are hoping there won’t be a next man up. Thielen hasn’t played in the last two games, has missed three of four, and he hasn’t been much of a factor at all in a month and a half. He also experienced what was called a “scare” with his hamstring on Monday that kept him out Wednesday. He was back on the field doing drills Friday and told the team’s website he’s “getting there.” He may be a game-time decision, but the Vikings don’t play until Monday at Seattle, so he has the extra day of rest.

8. Packers OT Bryan Bulaga
Status: Questionable (knee)
Level of Concern: Easing
Next Up: The Packers certainly have been planning for the next man up, promoting Yosh Nijman from the practice squad and claiming Jared Veldheer off waivers from New England. That was level of concern the club had in the initial days after Bulaga went down Sunday night against San Francisco. But after a reported diagnosis of a sprained MCL, the veteran returned to practice on a limited basis on Thursday, then participated in practice again on Friday. Green Bay is in New Jersey this weekend, playing a Giants team that offers the Packers the chance to rebound from last weekend’s loss rather quickly.

7. Giants TEs Evan Engram, WR Golden Tate, S Jabrill Peppers
Status: Out (Engram, foot; Tate, concussion; Peppers, back)
Level of Concern: Growing
Next Up: The Giants are not making the playoffs. And having multiple key pieces out with injury is nothing new for them, either. But at what point does a team go from dealing with the usual NFL injuries to feeling snake-bit? And each of this week’s injuries bring its own particular concern. Engram will now miss more than a month with his injury. Tate was emerging as Daniel Jones’ preferred target after missing the first four games with a suspension, and Peppers has a fracture in his back that only will heal with rest and could cost him the rest of the season.

6. Browns OT Greg Robinson, DE Olivier Vernon
Status: Questionable (Robinson, concussion; Vernon, knee)
Level of Concern: Growing
Next Up: The Browns head to Pittsburgh for their rematch with the Steelers, and they would like to have their offensive line at full health considering the Steelers likely will look to get after QB Baker Mayfield early and often. Not only do the Browns not know if they’ll have Robinson (who hasn’t practiced at all this week), but coach Freddie Kitchens won’t say whether the team will make the expected move of putting guard Justin McCray at left tackle should Robinson sit out. Vernon, who has missed the past three games, has practiced on a limited basis all week and could make his return.

5. Raiders WR Hunter Renfrow
Status: Out (ribs, lung)
Level of Concern: High
Next Up: This one hurts on multiple levels for the Raiders. Renfrow has emerged as the season has gone on, surpassing 50 yards receiving in four straight games in Weeks 8-11 after not doing it once in his first six games. He had five catches for 31 yards before he sustained a broken rib and punctured lung last week against the Jets, too. The injury, which could cost Renfrow the rest of the season, also hurts the Raiders from a timing perspective. They head to Kansas City just a game behind the Chiefs for the AFC West lead. Now may be the time for October trade acquisition Zay Jones to step up for Oakland.

4. Steelers WR JuJu Smith Schuster, RB James Conner
Status: Out (Smith-Schuster, concussion/knee); Doubtful (Conner, shoulder)
Level of Concern: High
Next Up: Conner was listed as out last week, so the change to doubtful alone should be good news for the Steelers. And Smith-Schuster cleared concussion protocol earlier this week. But neither player has been able to sufficiently get past what are multi-week injuries. And this week is the rematch with the Browns — against whom Smith-Schuster and Conner sustained (or aggravated) their current injuries. Once again, expect Jaylen Samuels and Benny Snell Jr. to get the work in Conner’s absence, while James Washington and Diontae Johnson likely will be the main targets for QB Devlin Hodges, making his second career start.

3. Colts WR T.Y. Hilton, RB Marlon Mack
Status: Out (Hilton, calf; Mack, hand)
Level of Concern: High
Next Up: Last week the Colts were in first place and getting Hilton back just in time for an AFC South matchup with Houston. Hilton did play, but the Colts lost nonetheless. Then Hilton sustained a setback at practice Wednesday, and he will be in street clothes Sunday for the fourth time in five games. With Mack still not back from a broken hand sustained two games ago, the Colts now sit a game behind the Texans and in jeopardy of falling to third in the division. Jonathan Williams has eclipsed 100 yards rushing in back-to-back weeks, but the Colts haven’t passed for more than 204 yards without Hilton.

2. 49ers WR Dante Pettis, DE Dee Ford, RB Matt Breida, OT Joe Staley
Status: Out (Pettis, knee; Ford, quad/hamstring); Questionable (Breida, ankle; Staley, finger)
Level of Concern: High
Next Up: The 49ers have been all about next man up with their vast depth, particularly on defense. But they’re likely going to need everyone they can get this Sunday in Baltimore. Breida has played only once since Halloween; Staley has played in only three games this season. San Francisco forced Aaron Rodgers into one of the worst games of his career despite Ford not playing, so the team can make do despite the injuries. But the 49ers are up against Lamar Jackson, so missing Ford could hurt. Also, Pettis injured his knee in practice Wednesday, leaving the team with little time prepare for playing without him.

1. Ravens C Matt Skura
Status: Out (knee — injured reserve)
Level of Concern: Anxious
Next Up: The Ravens have the NFL’s highest-scoring offense, but the center’s importance can be debated. Skura brought consistency to the line having started 36 straight games and playing the second-most snaps at the position since the start of last season. But Skura doesn’t grade out as highly as other members of the Baltimore line, and if the blocking does break down up the middle, QB Lamar Jackson has the ability to escape the rush. As for Skura’s replacement, undrafted rookie Patrick Mekari is expected to make his first start at center since high school, with newly signed Jake Brendel backing him up.