For many years, the surest thing about the Ravens has been their defense stopping the run.
When they held opponents to 3.6 yards per carry in 2014, it marked the 19th straight year they finished in the top ten in the league in that statistic. That's a crazy streak. Only in their inaugural season, back in the Memorial Stadium days, did their rushing defense not rank among the league's best on a per-carry basis.
When I came across that in the team's record book, I admit, it surprised me. I thought the run defense had gone through a valley of sorts a few years ago, and indeed, it ranked 20th in the league in yards allowed per game in 2012, the Super Bowl-winning year. And though it improved in 2013, it still didn't crack the top ten.
But the issue in those years was quantity more than quality, apparently, because in the most fundamental metric – yards allowed per carry – the Ravens have never fallen out of the top ten. They were No. 1 as recently as 2009, seventh in 2014.
It's not hard to figure out how stopping the run became such a Baltimore tradition, almost up there with crab cakes and the Preakness. The Ravens drafted Ray Lewis in 1996. He controlled the middle and didn't let many runners get by him. Within a few years, they also had Tony Siragusa and Sam Adams plugging things up. Haloti Ngata came along in 2006.
But now they're preparing for their first season in almost a decade without Ngata, their veteran anchor, a six-time Pro Bowler who was traded in March after contract talks failed to produce an extension.
Going forward without him constitutes quite an adjustment for the run defense. Ngata didn't pile up massive tackle numbers because the Ravens defense isn't organized that way; here, the front guys break things down for the linebackers to swoop in and make tackles. But Ngata's impact was still measurable in many ways. During his nine years with the Ravens, they allowed the fewest rushing touchdowns in the league and the second-fewest rushing yards per game. It wasn't a coincidence.
The run defense held up nicely when Ngata was suspended for the last four games of the 2014 regular season – one of the reasons he was traded – but it still has to prove it can handle the rigors of an entire season without its longtime resident immovable object.
The Ravens have invested a lot of personnel capital in making sure they're ready. They drafted nose tackle Brandon Williams with a third-round pick in 2013, tackle Timmy Jernigan with a second-round pick in 2015 and just selected Iowa's Carl Davis with a 2015 third-round pick earlier this month.
"Since I've been in Baltimore, I've always loved to get me a big defensive lineman," Ravens GM Ozzie Newsome said after the Davis pick.
Not all draft picks bear fruit, but Williams and Jernigan have quickly developed into major puzzle pieces with a lot of upside, and the Ravens graded Davis higher than where they got him. He certainly sounded ready for the challenge of pitching in to replace Ngata.
"Somebody has to carry the fire; somebody has to make the tradition go on, and why not be me?" Davis said on draft night. "He's a great player, but he's human, just like we are."
The Ravens also re-signed veteran Chris Canty, who can provide leadership, and they're expecting a slew of defensive interior players such as DeAngelo Tyson, Lawrence Guy, Kapron Lewis-Moore and Brent Urban to compete for snaps.
You can build a case for suggesting that stopping the run isn't as important as it once was. The Patriots just won a Super Bowl with a running game ranked 18th in the league. Other top AFC contenders such as the Indianapolis Colts (22nd), Pittsburgh Steelers (16th) and Denver Broncos (15th) also count on the pass more than the run.
But I don't think you can win regularly in the AFC North, where the Ravens reside, if you can't stop the run. The Steelers' Le'Veon Bell is one of the NFL's best young running backs. The Cincinnati Bengals ranked sixth in the league in rushing in 2014.
To advance out of that division into the postseason, the Ravens are going to need to uphold one of their most fundamental traditions and make opposing offenses sweat for every yard on the ground.