Von Miller joins Lindsay Czarniak on SportsCenter to discuss the battle for the Broncos' starting quarterback position and how Denver's defense will be pivotal to the team's success this season. (1:00)

ENGLEWOOD, Colo. -- Simmering below the surface of the ever-present public discourse about the Denver Broncos’ quarterback situation, the defending Super Bowl champions have a few additional questions to answer before the season begins.

Among those issues leading the way in the non-quarterback category is how things will look on the depth chart at running back for a team that has vowed to run the ball better. The rub is, as the Broncos have tried to decide who will be the quarterback, they have certainly let the fellas drop back and sling it around.

So far in the preseason, no team has thrown more passes than the Broncos’ 89: 44.5 per game. And after two preseason games, the Broncos are 19th in the league in rushing attempts with 53.

Broncos coach Gary Kubiak has admitted he has "let them throw it around a little bit," but said he isn’t distracted by the quarterback competition and is dialed-in on the other matters as well. Still, most of the questions from the outside that he faces day in and day out are about the quarterbacks.

“It’s easy for me to balance, because I have a lot of issues going on,’’ Kubiak said. “It’s hard for me to balance with you guys because that’s what you all want to talk about. When I walk up here, I can promise you there’s a lot of balance going on. … As a coach, your mind is always set for opening day. That’s where you’re trying to get your football team. That’s what I’m trying to do right now and also be able to make these decisions we have to make.’’

Some of the toughest decisions will come at running back. C.J. Anderson is the clear No. 1, but for the most part the Broncos have let the young guys lug the rock the most. Kapri Bibbs, battling to force the Broncos to keep four running backs in addition to fullback Andy Janovich, leads in preseason carries so far with 18. Rookie Devontae Booker has 13.

Kapri Bibbs (35), Juwan Thompson and Andy Janovich (32) wait their turn in running back drills on Aug. 8. David Zalubowski/AP Photo

Anderson and Booker have spent most of training camp and the preseason as the top two backs in the rotation. Juwan Thompson has largely been considered the third back because he has positional versatility, given that he plays both running back and fullback to go with his full slate of special teams.

Janovich will make the roster because the sixth-round pick is currently the only rookie listed as a starter on the depth chart. Like Thompson, he has a full docket of special-teams duties. If the Broncos keep three running backs and Janovich, that’s it.

The question is whether or not they will keep four in addition to Janovich. If so, then Bibbs and Ronnie Hillman, the team’s leading rusher in 2015, are battling for that last spot.

And those backs have all tried to show what they can do amid the Broncos’ festival of passes.

“I think we took a step [forward] last week,’’ Kubiak said. “ … Once you have confidence running the ball early, then you continue to do it. Runs at the end of the game tend to be longer because you’re fresh. You feel like you’re getting on them. Being persistent is one of the things we preach.’’

“When a guy gets in there and he’s doing his thing, you cheer him on because that’s all you can do,’’ Bibbs said.

The Broncos have had the ball plenty in their two preseason games -- 151 plays on offense in all -- but until they are comfortable with their decisions at quarterback, the running backs will likely have to make the most of their opportunities. The preseason finale at Arizona could be their time. With the Broncos’ starters expected to get their final work of the preseason Saturday against the Los Angeles Rams, the preseason game against the Cardinals could be the run-first affair the backs need to close things out.

“When it comes to a guy like me, I’m in there and I’m trying my best,’’ Bibbs said. “I hope those guys will encourage me and cheer me on the same way I will with them, because there’s nothing that they can do to stop my chances.”