ENGLEWOOD, Colo. — As the Denver Broncos’ offense changed its identity and point of emphasis in recent weeks, the defense remained the same — and remained among the league’s leaders, ranking first in yards allowed per play and yards allowed per pass play, second in yardage per rush and fourth in total yardage.

However, the expected return of linebacker Danny Trevathan could change things — potentially for the better.

When Trevathan succumbed to a leg fracture just below the knee during training camp, it appeared to deal a crippling blow to a linebacker corps that seemed to be short on depth after the free agent departure of Wesley Woodyard. But Brandon Marshall, a practice-squad player for most of the 2013 season, stepped into an expanded role and flourished.

Trevathan returned in Week 5 against Arizona but sustained another leg fracture, this one above the knee, the following week. Marshall stepped in and continued his earlier work, and he leads the Broncos in tackles with 47 more than anyone else.

“It’s been impressive,” Trevathan said, “but I already knew what was going down.

“Guys step up; B-Marsh came in here with the right mindset, he came out and grinded it out, started from the bottom, and you can’t do nothing but respect that. I came from similar backgrounds, you know what I’m saying, so I’m just proud of him, and we’re going to keep this thing rocking.”

Like Trevathan, Marshall is a sound fundamental tackler with good instincts and pursuit ability. Marshall is a bit stouter against the run, though, which could lead the Broncos to try to move him inside.

The Broncos tried to move Woodyard to middle linebacker last year after Trevathan emerged on the weak side, but the 233-pound Woodyard got engulfed in traffic and was eventually benched for Paris Lenon in the base defense, retaining his role in the nickel sub package.

If the Broncos can get Marshall and Trevathan on the field for every down, their linebacker corps could be the fastest in the league, with strong-side linebacker Von Miller filling out the trio.

“We’re going to fit together,” Trevathan said. “That’s speed out there. That’s athleticism. And that’s what the league has come to now, that kind of a third-down linebacker: quick speedster, be able to make plays, and we both fit in that category.”

Trevathan returned to practice two weeks ago, working on the scout team to get his conditioning up to speed. He is eligible to come off recallable injured reserve this week.

The question now is, will he?

“I’m not going to say I’m not or I’m going to play, but right now I feel good,” he said.

–With 16 names on their injury report — including eight who sat out practice entirely — the Broncos ditched their helmets and pads Wednesday, working in shorts, sweatpants and baseball caps.

“I think we needed it,” coach John Fox said. “It’s a point in the season where you want guys fresh. Their health and restoration off of a long season is most important.”

Among the eight players who sat out Wednesday were three wide receivers: Demaryius Thomas, Wes Welker and Cody Latimer. All were on the field watching practice when it began, but their absence left the Broncos with just two healthy wide receivers on the 53-man roster Wednesday: Emmanuel Sanders and Andre Caldwell.

Those who did practice went through preparation that was at least as much mental as physical, since no pads and no helmets meant no contact.

After Fox read the voluminous injury report at the start of his post-practice media briefing, a reporter suggested that it might have been easier for him to read a list of the players who were healthy rather than the ones who were not.

“I considered that, but we’re good,” he said.