Although headlined by relentless Pro Bowl defensive tackle Geno Atkins, the Cincinnati Bengals' defense is stingy on every level.
Coordinated by Mike Zimmer, the Bengals rank sixth in total defense and allow 317.5 yards per contest.
They're eigthh against the run, allowing 100.6 yards on the ground per game, and 10th in pass defense giving up 216.9 yards per game.
The Bengals are also tied for eighth in scoring defense, allowing 20.2 points per game.
"It's a really good defense, all over," center Matt Birk said. "They've got a great front four. We've got our work cut out for us. They've got a lot of tough people to block."
Led by Atkins' 13 sacks and four forced fumbles, the Bengals rank second in the NFL behind the Denver Broncos with 47 sacks, one less than Denver. With two sacks against the Ravens, the Bengals would set a new franchise record for most sacks in a season.
Defensive end Michael Johnson has 9 1/2 sacks followed by defensive ends Carlos Dunlap and Wallace Gilberry's five sacks apiece.
Johnson and Dunlap are rangy, tall defenders who make it tough for quarterbacks to see their passing lanes.
"They get after it," Pro Bowl offensive guard Marshal Yanda said. "They do a really good job."
At linebacker, the Bengals are led by undrafted rookie Vontaze Burfict and veteran Rey Maualuga.
Burfict has overcome conditioning and maturity issues in college at Arizona State that led to him going undrafted, recording 151 tackles this season to lead the Bengals.
Maualuga isn't far behind with 152 tackles and two forced fumbles.
Free safety Reggie Nelson has 79 tackles, three interceptions and two forced fumbles.
And former first-round cornerback Leon Hall has two interceptions, returning one for a touchdown last week in a 13-10 win over the Pittsburgh Steelers that earned the Bengals a wild-card playoff berth.
"That defensive staff is extraordinary," Ravens offensive coordinator Jim Caldwell said. "It's not your typical staff. Zimmer does a fine, fine job of adjusting. He's one of the best in the business. They have something to attack everything you do, and they do the same thing with protecting their good players as well.
"[Atkins] not the only threat. He's a great player, but I'm telling you, Johnson is a good pass rusher. Dunlap is outstanding. They have a linebacker corps that's out of this world and a secondary that is playing very, very well together. They create a lot of problems for you."
Getting Yanda back from a sprained right ankle provided a boost to the offensive line in a 33-14 win over the New York Giants.
The line allowed zero sacks and just two quarterback hits.
Yanda hasn't practiced this week due to knee and shoulder issues and could potentially be rested or have his playing time limited against the Bengals.
"Obviously, he's a big part of what we do," Caldwell said. "I think all of you realize that it's a collective unit and those guys play side by side. They work together. It's a cohesive group, and he's certainly a core to that group. He and Matt Birk in the middle, they are guys that we depend on.
"They do a tremendous job of rallying the guys and keeping everyone focused and calming the young guys down when needed. Very, very effective, obviously, it's demonstrated by the fact that he's made his second Pro Bowl. A talented guy that we are certainly glad he's back."