The Ravens will be missing three defensive starters, including nose guard Kelly Gregg, this weekend against the Tennessee Titans, who boast the NFL's eighth-best rushing attack.
Safety Dawan Landry (neck) and cornerback Samari Rolle (neck) are also listed as out on Baltimore's injury report.
Gregg is still working back from a knee injury that required surgery in August and caused him to miss the entire preseason.
He has not played in any regular-season contests, only practicing briefly for one day before significant pain revealed a hole in his cartilage. Head coach John Harbaugh said the team will evaluate Gregg on a week-to-week basis.
"We're sending his MRI pictures to a couple of other doctors," Harbaugh explained. "It's a very unusual injury from what I'm told. It's responding somewhat, and we just want to get another feel for what it is. We should know something this week more."
Gregg is confident he can return at some point this season, but rest is the best thing he can do for rehab.
"I had a setback a couple of weeks ago, but I'm working on coming back," Gregg said last week. "I'll be back this year. It's a slow process, but I've never dealt with anything like this."
The Ravens have started Justin Bannan in Gregg's place and still performed as one of the league's best run-stopping defenses. Bannan has 12 tackles, and Baltimore is the NFL's second-stingiest unit against the rush, only allowing 69.7 yards per game.
In the secondary, the Ravens are first-overall after giving up only 117.0 yards per game through the air.
But, they will be challenged when Fabian Washington and Jim Leonhard likely step in for Rolle and Landry, respectively.
Rolle and Landry were both injured in Baltimore's Week 2 matchup with the Cleveland Browns, a game where Landry suffered a spinal cord concussion and was carted off the field.
Landry had to wear a neck brace last week as he recovered from a knee-to-helmet hit, but was seen in the locker room Thursday without it.
The third-year safety also is eager to get healthy and play, especially after seeing his teammates get beaten 23-20 in overtime Monday night in Pittsburgh.
"It was hard to watch that," Landry admitted. "I had never been injured in my life, so that was tough. I don't take this time right now for granted. It's a blessing, and God has been good to me.
"The doctors haven't said anything about [not playing until] next year, so I'm taking it day-by-day and hopefully I can get back on the field soon."
Collins Presents Passing Challenge
After quarterback Vince Young sprained his left knee in the Titans' Sept. 7 season opener, Kerry Collins has stepped in to start and guided Tennessee to a sparkling 4-0 record.
Young, known for making as many plays with his legs as his arm, is a difference from the lead-footed Kerry Collins, a 14-year veteran.
But, Ravens defensive coordinator Rex Ryan is expecting the Titans to still get Collins out of the pocket in the passing game.
"I agree with you that you would expect a lot of drop-back from Kerry Collins," Ryan responded when asked to compare the two signal-callers. "We get that, but we also get a lot of bootlegs and things like that with him. So they're moving him around a little more than your typical drop-back passer.
"Hey, if we play sound fundamentally, if we do our job, we play to what we do defensively, I think we'll be fine."
Stover's Big Day
Matt Stover was looking to rebound against the Steelers after entering the game only 1-2 for field goals.
He responded with a two-field goal outing, hitting from 33 and 20 yards at Heinz Field.
Stover, 40, also placed two kickoffs in the end zone for touchbacks.
"He had a good night. He had two touchbacks, as you saw, and kicked the ball off well," said special teams coordinator Jerry Rosburg. "It helps our kickoff team when we get those kinds of balls to cover. I was highly impressed. He was excited about it. It was a good moment."
The Ravens are 8-7 in the regular season against the Titans and are tied 1-1 in the postseason…Baltimore has won five of the last six contests over Tennessee…The Ravens added guard Nathan Bennett out of Clemson and Lane wideout Edward Williams to the practice squad. Quarterback Casey Bramlet was released, while tackle Joe Reitz was placed on the injured list.