How many times have you seen an opponent backed up against its own goal line, ears splitting from the roar of M&T Bank Stadium, and drive at least 95 yards for a touchdown against the Ravens?

If you were born in 2002 or later, the answer is: never.

“That’s bad run defense, and that’s not who we are. It cannot be who we are.”

Ravens coach John Harbaugh

Until Monday night. When the Detroit Lions did it — twice. Two road-grading, clock-milking drives that ate nearly a quarter by themselves. Both ended the same way, too, with a Lions running back heading in for the score.

Not in a generation has the Bank been this easy to crack.

Based on the pure talent on their roster, the Ravens entered the season as Super Bowl darlings once again. But the biggest threat to their championship ambitions has nothing to do with Lamar Jackson’s mettle, John Harbaugh’s boldness or even Derrick Henry’s risk-taking.

The Ravens can’t stop the run — a fact that shakes the foundation of everything this team wants to do and achieve.

Especially without knowing how long they’ll be without former All-Pro defensive tackle Nnamdi Madubuike, it’s hard to view this problem as anything other than a fatal flaw.

“There’s nobody in that locker room that thinks that’s good enough,” said Harbaugh, whose team gave up the third-most rushing yards of his Ravens tenure. “That’s disappointing. That’s bad run defense, and that’s not who we are. It cannot be who we are. It’s just, it’s not going to be good enough.”

The Ravens left a lot to be desired in many aspects, including a pass rush that was again toothless (9 pressures, zero sacks), tackling that was sloppy (20 missed tackles) and coverage that was spotty (Marlon Humphrey got burned badly by Amon-Ra St. Brown on two of the game’s defining snaps).

But all these things stem from how the Ravens failed to stop David Montgomery and Jahmyr Gibbs, who especially ran with impunity in the second half. There was no moment more demoralizing than Montgomery’s scramble toward the right sideline for a 31-yard score, an appropriate capstone for a career-high 151 yards on just 12 attempts.

Baltimore’s defensive identity is based in physicality — when opponents come to the Bank, they expect to leave bloody and bruised. But it has been a long time since we’ve seen the Ravens’ run defense pushed around like this.

They hadn’t allowed 224 rushing yards since 2017. Just last year, they were the second-ranked run defense by yardage and allowed just one game — against rushing champion Saquon Barkley — of more than 125 yards on the ground.

But the Lions blew holes in the defensive front, pushing aside Travis Jones and Broderick Washington, testing the fading lateral quickness of Roquan Smith and the rookie sensibilities of Teddye Buchanan.

On Montgomery’s 72-yard run, rookie safety Malaki Starks was supposed to be the last line of defense — but when he tried to make the tackle, he got run over.

“Our run defense, it’s been pretty good the whole time I’ve been here,” safety Kyle Hamilton said. “But, when a team runs a ball like that, it just demoralizes you more than passing the ball.”

It’s important, too. The last five Super Bowl champions have had a top-10 rushing yardage defense, a top-10 rushing touchdown defense or both. It’s so essential for a champion to keep the opposing rushers out of the end zone, it’s almost taken for granted as a serious title-contending trait.

I’ve fretted in seasons past over the Ravens’ pass rushers, never quite believing the team’s edge guys were strong enough on paper to win it all. But somehow Chuck Smith has coaxed 114 sacks in the past two seasons with career years from vets including Jadeveon Clowney and Kyle Van Noy, a seemingly voodoo art. The Ravens have finished in the top two in team sacks each of those campaigns.

But the magic fades when the they can’t make their opponent one-dimensional, which they bitterly failed to do Monday night. Rookie Mike Green is still looking for his first career sack but acknowledged that part of the problem was that Baltimore didn’t force Jared Goff into many drop-back passing situations.

“We knew we were going to have to affect him in the pocket,” Green said. “I think it’s crazy because they got us in those situations where they didn’t have to drop-back pass. And so we didn’t have a lot of chances to rush the passer on drop-back passes. But we just gotta get them in them situations and take full advantage of them.”

As Harbaugh has said before: “You have to earn the right to rush the passer.” In their weak run-defense showing, the Ravens never earned it.

Madubuike is a huge part of that effort, disrupting the line of scrimmage and taking on blockers two at a time. In his absence, Detroit had no fear going inside. According to Next Gen Stats, the Lions ran between the tackles on more than 60% of their attempts, and the 156 yards they gained were the second most by any team this season.

Don’t let Ray Lewis, Terrell Suggs, Haloti Ngata or any of the other patron saints of run defense see what this group has become. It’s a sad sight. Even missing Madubuike and Van Noy, the Ravens acknowledge, is not enough of an excuse.

The Ravens haven’t given any indication of how long Madubuike will be out, aside from not yet placing him on injured reserve. Their one saving grace is that the upcoming schedule with the Chiefs, the Texans and the Rams is not exactly setting the world on fire in the ground game.

But in the ultimate test of what football is — two piles of guys trying to push the other back — the Ravens defense looks weak in precisely the spot that has been its strength for 25 years. A franchise that wears its run-stopping power as a badge of honor couldn’t keep a Super Bowl contender from running wild.

“We’re not trying to reinvent the wheel — we just have to go play football,” Hamilton said. “It’s probably not a good answer, but it’s running and it’s hitting. And we have to run and hit better.”

As much as any one flaw, that’s the one that will keep the Ravens up late on Saturday nights, wondering if they have what it takes to be a champion.