The first sign of trouble came with a not-so-heated discussion, before the floodgates truly opened. A simple 9-yard out from Jaguars quarterback Trevor Lawrence hit to Brian Thomas Jr. to further set up an end-of-half field goal, and he fell out of bounds, easy. Too easy. Broncos cornerback Pat Surtain II came over to discuss with safety P.J. Locke. Surtain’s hands splayed out. Something was amiss.

The second sign of trouble came with a punch to the mouth, with Denver already on the ropes. Jaguars wideout Parker Washington took another quick out in the third quarter, made Riley Moss miss, made Talanoa Hufanga miss, and strolled 63 yards down Mile High Lane. A touchdown later, and defensive end John Franklin-Myers trudged past a sideline of slouched shoulders, tugging off his helmet and going to chuck it. He thought better of it.

The third sign of trouble came with the finishing blow. Moss had Washington contained on a third-down grab in the fourth quarter, until he didn’t.  Washington spun away again for a 24-yard gain. Moss lingered on his knees for a beat. Then took his palm and smacked the ground in front of him.

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How many passing-game breakdowns have there been in recent weeks, for these Broncos?

“Too many,” head coach Sean Payton said, postgame.

Defensive players largely shrugged this off, after the Broncos’ three-month win streak was snapped Sunday night in a 34-20 loss to the Jaguars. Because what else is them for there to do? Denver’s still a 12-win team, as linebacker Alex Singleton pointed out postgame

“I’m not going to sit here and let you guys (expletive) on our parade,” Singleton chuckled. He grinned. His eyes didn’t really grin. “We have two games to go to be the number-one seed in the AFC.”

There’s no mistaking it, though: these Broncos have issues on the back-end to fix across those next two games and beyond, to play as deep as they’d like to. Lawrence picked defensive coordinator’s Vance Joseph scheme apart for four quarters, often sniffing out third-down blitzes and smoothly depositing the ball to his playmakers in a 23-of-36, 279-yard, three-touchdown performance. Payton said postgame that such a porous defensive performance “better be” an anomaly, and there’s plenty of reason to believe so.

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Look deeper, though, and Sunday was not as much an anomaly as an eruption of bubbling issues. In the last four weeks, quarterbacks have combined for an 89.7 rating against Denver’s defense. The Commanders’ Marcus Mariota freewheeled his way on some zone-read concepts against the Broncos a few weeks back. The Packers’ Jordan Love dinked and dunked with abandon in the first half in Week 15. Lawrence blew the top off on Sunday.

They’ve all exploited the same nagging issues that haunted Joseph’s unit down the stretch of 2024 — as teams have targeted Bronco linebackers and safeties in advantageous matchups for a solid month. Here’s a quick roundup of tight-end performances against Denver’s defense in the last five weeks:

— Chiefs’ Travis Kelce in Week 11: 9 catches, 91 yards, touchdown.

— Commanders’ Zach Ertz in Week 13: 10 catches, 106 yards.

— Raiders’ Brock Bowers in Week 14: 4 catches, 46 yards, touchdown.

— Packers’ Luke Musgrave in Week 15: 4 catches, 52 yards.

Another matchup-problem gadget weapon reared his head Sunday, as the Jaguars’ Brenton Strange went for five catches for 39 yards. He ran away from Broncos linebacker Dre Greenlaw for a 23-yard gain midway through the second quarter. A few plays later, he boxed out Locke — with a bit of an obvious push-off — for a short touchdown.

“They scheme up plays pretty nicely,” Locke said, asked about problems containing tight ends and running backs in the passing game. “That’s it.

“I don’t think it’s problems. I don’t think it’s problems. That’s stuff we just gotta handle.”

Jacksonville head coach Liam Coen, though, repeatedly and obviously aimed at Bronco holes in coverage Sunday with a variety of targets. Greenlaw has been a step slow on a couple routes in recent weeks. Locke was effective against the run in his first start of the season at safety, but was picked on on a late-first-half field-goal drive by Jacksonville. Communication errors abounded, too, as Jacksonville went eight-of-15 on third downs.

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On a short week before travelling to Kansas City for a Christmas Day game, the defense will gather to watch film Monday, Singleton said. They have overcome some early-season missed handoffs in match coverage before. And Singleton, for one, wants his unit to feel it, as he said.

“Like, am I happy about today? Not at all. It’s embarrassing,” Singleton said. “We shouldn’t do that. We need to play better. We need to get off the field. We need to make the plays.”

Just like 2024, however, the Broncos’ ability to make such plays will hinge on their health and stability at those two positions being attacked by play-callers: linebacker and safety. Denver signed Hufanga and Greenlaw in free agency to help beef up the Broncos’ coverage over the middle of the field. But Greenlaw suffered a hamstring injury Sunday after an already injury-plagued season, and Denver’s best coverage safety in Brandon Jones is on injured reserve.

There was plenty of verbal confidence from this Broncos defense in the locker room, on Sunday night. There was also a slight air of a unit shell-shocked.

“We gotta just stay in the fight, just keep going,” outside linebacker Jonathon Cooper said. “So we’ll figure out how to get better from this, for sure.”

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