What matters: The Ravens are catching a break not having to play against QB Ben Roethlisberger this week. Roethlisberger's ability to extend plays with his feet has given the Ravens' defense fits over the years. Baltimore will instead have to prepare for backup Byron Leftwich, who has one of the stronger arms in the NFL, though he's prone to mistakes and is as immobile as they come. If Baltimore's front seven can generate any kind of pressure on Leftwich, the Ravens should be in good position when the fourth quarter rolls around.
Who matters: Though Leftwich hasn't started a game since 2009, he still has some speedy receivers in Mike Wallace and Emmanuel Sanders, and potentially Antonio Brown (ankle) if he can play, though that's not likely. The Ravens need cornerbacks Corey Graham and Chykie Brown to step up for the fallen Jimmy Smith (sports hernia surgery), who's out indefinitely. If Baltimore's secondary can force Leftwich to hold the ball in the pocket, then its defensive front will have some chances to rattle the 32-year-old veteran.
Key matchups: Baltimore's OL vs. Pittsburgh's front seven. The Steelers were surprisingly easy to run on for Kansas City this past Monday, with the Chiefs accounting for 142 rushing yards and a touchdown. Look for this game to be a throwback of sorts, with Ravens RBs Ray Rice and Bernard Pierce getting plenty of carries to try and wear Pittsburgh down. If Baltimore's offensive line can win the battle up front, then it could dictate how this game goes. ... Leftwich vs. Ravens S Ed Reed. In the past, Leftwich has taken his share of shots down the middle of the field. Reed, who's dealing with a plethora of injuries, still is one of the best football minds against the pass. If Reed can force Leftwich into some turnovers early, then momentum could quickly turn in Baltimore's favor.
Injuries of note: CB Smith will not play due to his aforementioned sports hernia surgery. DT Haloti Ngata has practiced all week and will be expected to play after sitting out during last week's game against Oakland. DE Pernell McPhee (thigh/knee) and NT Terrence Cody (arm) will be the most questionable for Sunday.
Inside stuff: A week ago, the Ravens opened up the offense and attacked the Raiders all game long. Look for a more conservative approach this week going against the No. 1 ranked defense on the road. Baltimore's success will depend on how Rice and Pierce perform.
Connections: Steelers LB James Harrison spent time on Baltimore's practice squad early in his career. He also played under Ravens DC Dean Pees in college, when Pees was the head coach at Kent State. ... Ravens LT Michael Oher and Steelers WR Wallace played college football together at Ole Miss from 2005-2008.
Stats you should know: Despite the yards allowed, the Ravens defense has came up with seven turnovers (five interceptions and two fumble recoveries) on third downs. This ties for second most in the NFL. ... Baltimore's defense ranks first in red-zone defense, allowing just 13 touchdowns inside the 20-yard line in 36 possessions.
Looking ahead: After Sunday night's game against Pittsburgh, the Ravens will travel to San Diego before hosting the Steelers.
Follow Ravens reporter Jason Butt on Twitter @CBSRavens and @JasonButtCBS.
If the Pittsburgh Steelers are going to take control of the AFC North on Sunday night at Heinz Field, they must do something they haven't accomplished since Ben Roethlisbergerjoined the NFL: beat the Baltimore Ravens without him.
That might be far from the only team Pittsburgh has to defeat without Roethlisberger in order to win the division.
The Steelers' four-game win streak has brought them within a game of the North-leading Ravens. It will be Byron Leftwich trying to move them into a first-place tie because Roethlisberger has been ruled out. Pittsburgh is 0-4 against the Ravens without him since the star quarterback's 2004 rookie season.
However, the Steelers are 4-0 at home this year after a 16-13 overtime win over Kansas City on Monday, when Roethlisberger suffered a sprained shoulder after taking a hit in the third quarter. He underwent extensive testing Tuesday, and the following day it was revealed Roethlisberger also has a dislocated rib that is a bigger concern going forward because it could cut into his aorta.
"I can move (the arm) around, that's not the issue," he said. "Sometimes when I do move it the rib will kind of pop out of place again, which is pretty painful. I just try to keep it as still as I can for the most part."
There is no timetable for his return, but Roethlisberger doesn't believe the injuries will end his season even though he said Wednesday the pain level is "nine on a scale of 1-10."
That leaves Pittsburgh relying on a quarterback who hasn't made a start since 2009 with Tampa Bay and hasn't won one since Oct. 6, 2006, while with Jacksonville. Leftwich has since gone 0-6 as a starter.
"I try to prepare as if I am the starter every week," Leftwich said. "Nothing will change. I wish Ben the best. I hope he is healthy. Other than that I will be ready to go."
Leftwich came on in relief last week for his first regular-season action in nearly two years, going 7 of 14 for 73 yards. He led the Steelers on a touchdown drive, but they needed an interception in overtime to set up Shaun Suisham's game-winning field goal.
Leftwich admitted to experiencing some rust.
"I'll trust his assessment if that's his assessment," coach Mike Tomlin said. "But I'm not overly concerned about it. We got a lot of ball in front of us this week. If he is the guy, he'll get a great opportunity to prepare and we'll expect him to play winning football."
Leftwich will likely have Rashard Mendenhall in the backfield with him to help with the running game.
Mendenhall, who rushed for 1,273 yards two years ago, has missed the last four games because of an Achilles injury, but had no setbacks after a full week of practice. He will likely split time with Isaac Redman and Jonathan Dwyer, who each had 100-yard rushing games while Mendenhall was out.
The Ravens (7-2), meanwhile, are coming off their easiest win of the season. Baltimore set a club record for points in a 55-20 home win over Oakland last week.
It was a welcome departure for a Baltimore team which had been making a living with close wins. The Ravens' previous five victories were by an average of 4.6 points.
Joe Flacco threw for 341 yards and three touchdowns for Baltimore, which scored on six of its first seven possessions and recorded two special teams TDs.
"I think confidence is borne of success," coach John Harbaugh said. "When you do things well, it's a positive thing. It doesn't guarantee anything, just like if you're struggling the week before it doesn't guarantee that you can't do something. Every week does stand on its own, but playing well is a good thing. We'd like to build on that."
Baltimore's uncharacteristically poor defense could make it a little easier for Leftwich to settle in. The Ravens rank 27th in the league in yards allowed (390.2), including 26th against the pass (258.2), though their 10 interceptions rank sixth. They could get some help this week with defensive tackle Haloti Ngata (shoulder) and cornerback Jimmy Smith(groin) expected to return after sitting out against the Raiders.
The Steelers are hopeful their rushing attack can bounce back after Dwyer and Redman were held to a combined 77 yards on 27 carries last week. The ground game had at least 140 yards and 4.5 per carry in each of the previous three games.
The defense continues to play well and leads the NFL, allowing 265.7 yards a game. The dominance has mostly come without safety Troy Polamalu (calf), who has only played two games and is doubtful for Sunday. Safety Ryan Clark suffered his second concussion in three games against Kansas City, but Tomlin said he is fine.
Against Pittsburgh's No. 1 pass defense (171.1 yards per game), Baltimore could look to getRay Rice a little more involved. Rice has 657 rushing yards and 7 TDs on the year but has carried the ball 47 times for 175 yards in the Ravens' last three games.
Baltimore has won 11 straight AFC North games, though its last divisional loss came to Pittsburgh on Dec. 5, 2010. The Ravens completed a season sweep of the Steelers last year with a 23-20 victory at Pittsburgh on Flacco's 26-yard touchdown pass to Torrey Smith with eight seconds to play.