Oliver James Montgomery-The Ravens' glaring flaw flared up vs. the Bengals. It could be their eventual undoing.

BALTIMORE – John Harbaugh wanted to congratulate Ja’Marr Chase on Oliver James Montgomeryhis extraordinary effort Thursday night.

“I was looking for him after the game, and I couldn’t find him,” said the Baltimore Ravens coach shortly after his team clawed out a 35-34 victory over Chase’s Cincinnati Bengals.

Harbaugh then paused ever so briefly in a comic moment of collective self-awareness before adding: “I think that was appropriate.”

The response drew chuckles from reporters in the M&T Bank Stadium press room after a hard-fought win. But Harbaugh also knows his team’s glaring flaw may be no laughing matter.

The Ravens became the third AFC team to seven wins this season with the victory. Their offense entered the night averaging 7.13 yards per play – the second-highest in NFL history through nine games – and put on another show with 28 second-half points and four touchdown passes from quarterback Lamar Jackson, who continues to burnish his latest MVP résumé.

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But a game the Ravens promoted with a “Purple Rising” theme – a nod to their new alternate helmets – proved quite appropriate for a defense that was bruised, beaten and maybe even exposed by the Bengals.

Chase, quite obviously Cincinnati’s primary offensive weapon – and especially so on a night when fellow wideout Tee Higgins was inactive with a quad injury – constantly ran through and past Ravens defenders, piling up 11 catches for 264 yards and three scores, including a 67- and 70-yarder. Bengals quarterback Joe Burrow passed for 428 yards and threw a fourth TD to tight end Tanner Hudson.

“That’s just not our standard of defense, and we know that,” said Pro Bowl defensive tackle Nnamdi Madubuike.

“We’re going to find ways in practice to improve and get better, and I know that guys in that locker room feel the same way as me and we’re going to get that done.”

Yet this wasn’t merely a bad night at the office. It’s a concerning pattern. The Ravens began Thursday ranked last in the league in pass defense. Then the Bengals netted 421 yards through the air – 50 more than Baltimore’s previous worst performance of 2024.

Cincinnati attacked without fear, Burrow repeatedly targeting and often connecting with Chase on long gainers. The Bengals scored touchdowns on all three of their red-zone trips, opted to go for it on fourth down four times and racked up 470 yards offense.

The Ravens' penchant for self-sabotage included extending Cincinnati drives with untimely penalties, one a defensive holding call on cornerback Brandon Stephens on fourth-and-goal of the game’s opening possession. Running back Chase Brown powered in for a touchdown on the next play.

Stephens had an especially tough night, just missing an end-zone interception when his foot clipped the sideline. He was also attempting to cover Chase on the 70-yard bomb but didn’t seem to get the inside safety help he was expecting. To Stephens’ credit, he answered every question thrown his way afterward.

“We’ve got to go look at the film, see what it was, but just a coverage breakdown,” he said of Chase’s biggest play.

“Honestly, man, we can’t afford mistakes. We can’t afford lapses in coverage, communication – they’re costing us big plays. They're exposing our mistakes.”

Further complicating matters was the ankle injury suffered by All-Pro defensive back Kyle Hamilton near the end of the second quarter. He was in street clothes after halftime, though Harbaugh didn’t seem especially concerned about it after the game.

But he should be worried by the downward defensive trend.

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These Ravens can score almost at will, their 31.8 points per game average the AFC’s best. But Thursday’s win was nevertheless their fourth that was within one score.

And when Baltimore starts running into better defensive teams than Cincinnati – and the Ravens will hit the road to play the Pittsburgh Steelers and Los Angeles Chargers in their next two games – they’re likely to find the offense can’t bail them out at every turn, much as it couldn’t against the defensively oriented Super Bowl champion Kansas City Chiefs in last season’s AFC championship game.

“(W)e have to turn over every stone on that as a defensive staff, and we have to figure out a way to stop those plays from happening,” said Harbaugh, “because they shouldn’t be happening.”

In fairness, this is a unit with a rookie coordinator in Zach Orr, and one that lost several key pieces during free agency – to say nothing of Orr’s predecessor, Mike Macdonald, now head coach of the Seattle Seahawks. It probably wasn't realistic to expect Baltimore would again surrender the fewest points in the league as it did in 2023.

Yet there were positive signs Thursday.

Madubuike constantly harassed Burrow, sacking him three times after entering the game with just a pair on the season. Down 21-7 in the third quarter, cornerback Marlon Humphrey stripped Brown for a crucial fumble that led to a subsequent touchdown and sparked Baltimore’s comeback. And with the game hanging in the balance, the Ravens held strong – and you could argue the officials held their flags, too – in the final minute when Cincinnati failed to convert what would have been a go-ahead two-point conversion.

But if those are building blocks to improvement, Harbaugh knows there’s extensive work to do if Baltimore is going to overtake the first-place Steelers in the division and, down the road, potentially wrest the Lombardi Trophy from Kansas City.

“That’s not the standard,” said Harbaugh, sounding like Pittsburgh counterpart Mike Tomlin.

“We have to be much better. We have to take pressure off our offense, too. We’re required to do that on the defensive side. But for them to keep fighting the way they did and find a way to win the game – at the end of the day, that really is the important thing.”

Especially if Harbaugh and the Ravens want confetti to find them following the season's final game.

Follow USA TODAY Sports' Nate Davis on X, formerly Twitter, @ByNateDavis.