The only noise emanating from the visiting locker room underneath Miami’s Hard Rock Stadium was Sean Payton’s shouting as he ripped into his team.

Equal parts bewildered, embarrassed and enraged after a 70-20 loss to the Dolphins, he made it clear in no uncertain terms that this could never happen again.

Giving up 70 had only rarely happened in NFL history as it was, and 726 yards felt like double that as Miami rolled to 10 touchdowns in the 50-point blowout.

Once Payton left the room, a ringing silence set in.

After a small group of reporters around Alex Singleton dissipated, he quietly asked one, “Was it the worst of all time?”

The worst in franchise history, no doubt. At 0-3, the Broncos defense looked on a collision course with all manner of dubious distinctions.

Seven weeks later, the vibe could hardly be more different.

On Monday night in Buffalo, Payton emerged from the visiting locker room after a last-second triumph and had to speak up at the podium as the music blasting from the adjoining room rattled the lectern he stood at.

A third straight win could hardly have been forecast even a month prior. Doing it on the strength of a defensive surge? Unthinkable.

“It was kind of just like, ‘Oh, ok, we’re back in it,’” Singleton told The Denver Post.

How did it happen? How did a defense off to one of the worst starts in NFL history turn into a potential top-10 group? Why did it take so many weeks to make a series of moves that have panned out so well?

And does this group have the chops to take a four-game run and turn it into a real playoff chase?

The next two weeks will tell a lot, but the Broncos defense has already turned its season around in a major way.

Early reckoning

After the 50-point loss to the Dolphins, Payton and defensive coordinator Vance Joseph vowed to evaluate the course they set to start the season.

Instead of making a rash decision about Joseph’s job status, though, the brain trust went to work figuring out how to put Denver’s defense in better situations.

“We all took a hard look,” secondary coach Christian Parker told The Post. “The players took a hard look at how they were executing and studying and preparing. We took a hard look at ourselves in terms of the schematics, our process during the week, our meetings and everything else.

“Some things, it was like, ‘OK, we feel good and have to stick with the process.’ Some things we needed to change.”

Part of that change was trimming the defensive call sheet. That’s a natural process during a season, particularly with a new coordinator, but the Broncos really needed it. They had too much thinking on their plates and too little clarity. They looked slow and stagnant in the early weeks.

No longer.

The Broncos’ DVOA, a defensive efficiency metric, was among the worst in recorded NFL history over the first five weeks, according to FTN data. Over the past five weeks across the league, the Broncos are ranked ninth.

“Now we’ve just got a smaller (set) of things we like to do and we feel comfortable doing and we’re maximizing doing those to the best,” outside linebacker Baron Browning said. “We’ve got great players, so you don’t want to overload them with information.

“You give them the smallest amount of information possible and then you just let them go play.”

That slimming down aligned generally with the time it took for Joseph, his assistants and the players to really start to understand each other.

“It takes time to get on that same page. We had to take some time to get to that,” Parker said. “There were multiple reasons. That wasn’t the primary reason we struggled early, but certainly I think Vance has really settled in. He’s been able to verbalize exactly what he sees and how and why he’s calling certain things, how he wants to call it.

“The guys have been able to really sink their teeth into it and we’ve been able to practice that way and watch film that way and meet that way and we’re able to produce at a high level now.”

As that process played out, Denver also decided it needed to make some moves.

Swapping parts

Consider the way the Broncos’ defensive depth chart looked against the Dolphins on Sept. 24.

Safety Delarrin Turner-Yell and cornerback Damarri Mathis played every snap.

Outside linebacker Randy Gregory played 34, while Frank Clark, signed in June as a free agent, missed the game due to a hip injury.

Essang Bassey played 48 snaps at nickel, while Jonathan Harris played 50 up front compared to Mike Purcell’s 34.

Today, Gregory plays for San Francisco and Clark for Seattle. The group turned over to a quartet of young players. Bassey was released after Week 4 and second-year man Ja’Quan McMillian has blossomed into a play-making machine in the slot. Mathis lost his job in Week 7 and now is the dime defensive back, supplanted by veteran Fabian Moreau. He’s played every snap outside the past three weeks and, according to Parker, is, “a very aware player. He communicates great and he’s a very even-keeled player who settles the boat.”

Turner-Yell was forced into action early in the season and again Monday at Buffalo due to a run of injuries at safety, but is functionally the fourth option when Justin Simmons, Kareem Jackson and P.J. Locke are healthy.

The defensive line change is more subtle, but Purcell’s provided stouter run support on early downs in recent weeks as he gets further removed from an offseason knee injury and early-season rib issues. He’s started three of the past four games, while Harris’ usage has dropped.

Fast enough?

Every one of those moves has paid off for Denver.

“Injuries early killed us,” Singleton said. “Some guys that shouldn’t have been playing were, stuff like that. It’s just a lot has changed and it’s helped a ton.”

Could some of them have been made sooner?

The wheels fell off quickly with Gregory and Clark, but Browning didn’t return from offseason meniscus surgery until Week 7. The Broncos were strapped depth-wise at safety, too. Locke started the year on injured reserve with a dislocated toe and then Caden Sterns played two snaps before tearing his meniscus Week 1. Simmons missed most of camp with a groin/hip injury, then reinjured it in Week 2 and missed defensive meltdowns in Miami and Chicago.

Denver could have made the change with Mathis or Bassey sooner, but after seeing Mathis play well down the stretch of his rookie season, the Broncos thought he’d come around.

“It’s just off of feel and it’s not an emotional decision,” Parker said. “It’s based off of what you show on the grass and how guys are handling things and production. Guys understand that going into it. That’s how it’s measured, that’s how we’re all evaluated. We just had to make a decision and roll with it. He understood. Wasn’t happy about it, of course, nobody’s going to be, but he’s never been disruptive. He’s still one of the guys and he’s just been practicing and preparing for his next opportunity.”

Moreau played just 28 snaps in the first six games and was inactive Week 5. Since entering the starting lineup, he’s provided steady play and a big interception against Josh Allen on Monday night.

McMillian’s rise has been even more impressive. He was a healthy scratch Week 1 and played a total of six snaps the first three weeks before taking over for Bassey and providing an immediate upgrade.

In the past four games alone he’s logged five tackles for loss, an interception and forced a fumble on the first play of the game against the Bills.

“He plays the game so hungry and he just shows up week after week making big plays,” Moreau said of the undrafted second-year man out of East Carolina.

The biggest change

No single player has had a bigger impact on the Broncos’ defensive turnaround, however, than Simmons.

Since he returned in Week 5, the results are night and day. Denver surrendered 234 rushing yards to the Jets in his first game back, but even then the defense gave up just one touchdown. It wasn’t their finest work — Nathaniel Hackett’s offense had the ball for nearly 35 minutes — but it was a start.

Simmons has gone on a tear since.

The big plays, of course, jump off the screen. He’s been in on five turnovers in the past four weeks: three interceptions, a forced fumble and a fumble recovery. But it’s everything else he does that has helped Joseph’s unit take off.

“He is the quarterback,” Parker said. “Justin’s command is at a very high level. He has his PhD.”

Here’s how communication on Denver’s defense works: The call goes from Joseph into inside linebacker Josey Jewell (or Singleton when Jewell is out) and Jewell relays the call to the defense. Then Simmons takes that call and adds coverage details and potential checks to the back two levels. In the slot, McMillian takes charge of how the Broncos want to handle stacks, bunches and unique alignments by the receivers.

Having one of the best safeties in the game fully healthy and surveying every play alters the confidence level of everybody around him, too.

“Me and Justin talk every single play,” Singleton said. “It’s almost like unspoken communication a lot of the time but then also there’s just so much communication. Before the snap, I’m turning around and talking to him 90% of the time and we’re not even looking at the play a lot of the time.

“So much of it is just, if we can be in the right spot, we can beat anybody. It doesn’t really matter what the offense does. It’s so much of that and between the four of us with (Kareem Jackson) being back now, it makes it so much easier.”

The sustainability question

Any small subset of games is going to have variance.

In splitting a pair of games with Kansas City, Denver’s defense allowed just one touchdown to Patrick Mahomes and company in eight red zone trips.

Over the past two weeks, they’ve forced nine turnovers plus two fourth-down stops.

Good defenses are stout in the red zone and consistently take the ball away, but neither of those rates are sustainable over the course of an entire season.

So, what will happen when Denver doesn’t take the ball away several times? Is the group up to that kind of grind-it-out task?

Buffalo still ran for 192 yards against Denver. The Bills and Green Bay each generated go-ahead, fourth-quarter touchdown drives in crunch time.

Singleton said he thinks the win against the Packers represents, “the base,” of expectations for the rest of the season.

“Obviously it would be great if we get a turnover on the first play of the game and on the second drive and do that kind of stuff, but if we don’t, we’ll be fine,” he said. “We’ve been able to hang our hat the last four or five weeks on winning third downs. If we get off the field like we have been, it won’t matter if we don’t get as many turnovers. And the red zone. Obviously, this past week we weren’t as good as we have been, but overall we’ve been playing pretty well in the red zone and those count as takeaways, too.

“It’s a four-point play when you get off the field down there.”

Confidence men

It might seem like the Broncos’ defensive fortunes changed on a dime — or maybe a nickel — but it took schematic adjustments, reorganization, jettisoning two veterans, swapping out several others, getting healthy and more to turn a sinking ship into a seaworthy vessel.

Perhaps some early season struggle should have been expected considering the coordinator change and Simmons missing so much time in camp, but everybody involved talked almost exclusively about a smooth transition.

Even then, nobody could have anticipated giving up 160 points in the first four games.

Now that it’s in the rearview mirror, Broncos players insist they’re not looking back.

“I just think we knew the defense we could be,” Singleton said. “We just kind of, whatever we were doing those first few weeks was just kind of out of character for a lot of us. And then I think for whatever reason — one is I think Justin came back and Josey came back the same week, and we got the communication down that week — it just kind of clicked.

“We got back to who we were all last year, who we were in camp and who we should have been.”

Broncos defensive turnaround

The Denver defense has undergone a dramatic turnaround over the last four games, which includes its current three-game win streak. Here’s a look at the numbers:

Broncos pass defense

Broncos run defense

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