ENGLEWOOD, Colo. – The Broncos face another tough NFC West opponent on Sunday. Coordinators Adam Gase and Jack Del Rio discussed what they are expecting from Jim Harbaugh's 49ers.

ANOTHER TOP DEFENSE

Despite losing multiple key starters on defense, the 49ers have managed to maintain their status as one of the top defenses in the NFL. San Francisco currently ranks second in yards allowed per game, fifth in rushing yards and second in passing yards in the NFL.

Gase and the Broncos offense have had their fair share of tests this season as they have faced two of the best defenses in the NFL already in the Seahawks and Jets. And they're only five games into the season.

"Yeah, another top 5 defense, we love seeing them," Gase said, laughing. "Obviously this group is very physical up front. Starts with Justin Smith. Just him and Ray McDonald—I was with both those guys in '08 and it hasn't changed. Up front, stout, and then just that whole group they have in the linebacking corps, they're physical as well. That front seven is a tough group to go against."

Gase was an offensive assistant for the 49ers in 2008 where he got to know those dynamic playmakers. Despite the plethora of injuries that the 49ers have incurred, Gase isn't surprised by the success they've maintained because of their excellent coaching staff.

The 49ers have only allowed an average of 20.5 points per game and just 287.2 yards.

Patrick Willis and Jimmie Ward both suffered injuries during the 49ers' Monday night win and their status for Sunday's game is unclear. The 49ers are already playing without NaVorro Bowman, Aldon Smith and Tramaine Brock.

When asked if the NFC West teams have been more physical than other divisions, he couldn't say. But he did know that the Broncos' schedule hasn't been easy and it won't let up with the 49ers.

"Every game we've played, we've come out of that game going, 'That was a good group.' A lot of the teams that we've played earlier—the Colts, seems like they're on a pretty good roll," Gase said. "Arizona's tough, Kansas City's absolutely tough, and this Jets team, they were no joke. So we've played some tough teams and obviously Seattle is what they are."

WAITING FOR THE BIG RUN

The Broncos' longest run this year so far this season was a 26-yard burst from Ronnie Hillman during the Sunday's win over the Jets. At the end of the run, he fumbled the ball but it was recovered by Andre Caldwell. But the Broncos running back corps are still waiting for more consistent, explosive runs.

Ronnie Hillman had 100 yards on Sunday during his first NFL start.

"I think he did a good job of hitting the holes that were there and Ronnie has an unusual speed," Gase said. And he gets through the hole quickly and all of a sudden he's in the secondary. Now if we get to the point where we can actually make a safety miss one of these days, it's probably going to be more. So that's something that we've been working on. But just his speed is something different than what we've had in the past and if we can keep him going, it should be good for us."

Hillman said he isn't "looking for the home run," but he is certain that he will break out at some point soon and cause an opponent to miss.

"It could happen any time," Hillman said. "You don't want to create a long run—you just kind of want it to happen. If you do what you do and you're in the right spot every time, eventually one of those guys is going to be undisciplined and scrape under or over and it's going to be right there for the home run."

TAKING ON "HYBRID" TIGHT ENDS

The Broncos' defense is accustomed to taking on top tight ends as they are tasked with containing the NFL's touchdown leader in Julius Thomas every day at practice. The Broncos have faced some tough tight ends so far this season, especially in Jace Amaro and Travis Kelce, but veteran Vernon Davis will certainly challenge the Broncos' defense.

Jack Del Rio said the Broncos will have their "work cut out" for them in containing Davis on Sunday night.

"You've got a bunch of different weapons within their group and he's certainly one of them," Del Rio said. "He's back healthy—I know he had a couple games where he wasn't available—but he's back in the lineup and certainly somebody that we've got to account for."

Del Rio said there are "hybrid" players in today's NFL that are bigger than receivers but still fast. Thomas and Davis are two of these special tight ends and he considers them "real weapons."

It is never an easy decision when determining who will cover powerful tight ends like Davis and Thomas.

"It's just part of what we do," Del Rio said. "Part of what we do as far as looking at ourselves, looking at them, trying to put our guys in position where they can be successful. They do a lot of different things and they do a lot of it well. They've got a big offensive line. We've got to get good production out of our front against that line. They've got good skill people; we've got good skill people, too. We've got to get good production against that group. We've got our challenges set and so do they. But it should be a heck of a game."

NELSON EARNS PLAYING TIME

With Danny Trevathan placed on short-term injured reserve, Corey Nelson was promoted to work as the Broncos' second nickel linebacker. The seventh-round pick led the Broncos in tackles on Sunday and is proving to be an asset.

Del Rio said Nelson earned his way on the roster and onto the field through his performance on special teams.

"We're finding ways to do things with him in practice, and he does it well in practice," Del Rio said. "Then it just adds to the confidence, so when you get to games, you're not afraid to put him in. And we like to create packages where we get our guys in—it may be in a smaller role—and if they do well, we build the role. So we had that in mind with him and it happened to coincide with Danny going down, so it worked out pretty well"

He said when players are worked in for smaller roles, they stay engaged and are prepared to go in the game if necessary.

"We stress a lot of fundamentals throughout the week with all of our guys and I think doing that and understanding how everybody fits together is important to us as we grow," Del Rio said.