ENGLEWOOD, Colo. -- Few teams have both expended the resources and reaped the rewards of that investment as the Denver Broncos have done in their defensive secondary.

In their “No-Fly Zone," a group that has led the league in pass defense in each of the last two seasons, they have two homegrown players in Chris Harris Jr. and Bradley Roby to go with three free-agent signees: T.J. Ward, Darian Stewart and Aqib Talib. Four of those players have gone to the Pro Bowl at least once in the last two years -- Harris, Talib, Ward and Stewart.

In short, the Broncos have gotten what they’ve paid for to this point.

“I think it’s the best secondary in the league," linebacker Von Miller said. “I know those guys are the best secondary in the league. [Roby] could start almost any other place."

But the Broncos have tried to construct some depth behind all of that roster wealth as well. Though the Broncos’ starters and Roby don’t come off the field much and have largely had the good fortune of good health, the Broncos like the progress of what safety Justin Simmons called “the Baby No-Fly" this past week.

Simmons and Will Parks, both safeties, were in last year’s draft class. Cornerbacks Lorenzo Doss and Taurean Nixon were in the 2015 draft class. Cornerback Brendan Langley was in this year’s draft class. That’s a collection of five homegrown players the team hopes can be future starters.

“We work those guys," Harris said. “They know when they go in there, there can’t be a drop-off. They have to be ready to play."

Whether or not the Broncos need them in the months to come remains to be seen. Ward is in a contract year -- the final year of a deal he signed in 2014 -- while the six-year deal Talib signed in 2014 carries salary cap figures of $12 million this season and next.

And in 2019, when Talib would be 33, he’s scheduled to count $8 million against the cap. Still, Talib’s 2016 efforts kept him among the league’s elite at the position, so the Broncos continue to believe his contract reflects his play.

But as executive vice president of football operations/general manager John Elway routinely says, he’s “looking four, five years down the road." And the Broncos’ secondary in 2017 could offer a glimpse of the future at times, especially with Simmons. Simmons started three games last season, played in 13 on defense and played just over 31 percent of the defensive snaps overall.

Simmons, with another offseason to work through some of the inevitable rough edges that arrived as a rookie, believes he could be ready for some more situational duties or to cover for any potential injuries as well.

“It wasn’t like they were pity snaps; they were snaps to get us into the postseason," Simmons said. “... So many things I just missed, for lack of a better word, because I was trying to survive through that time. I was trying to make sure I was just in the right place at that right time instead of stepping up and making plays."

Parks, who could face some league discipline at some point because of a March arrest on misdemeanor domestic violence charges, played in 16 games last season. And by the end of the season, he had played 23.5 percent of the defensive snaps.

Doss will get a long look as the team’s fourth cornerback after Kayvon Webster’s departure in free agency and the Broncos have been particularly excited about Langley’s potential during their offseason workouts, given his top-shelf speed. It all means youth will certainly be served on the depth chart behind one of the most accomplished groups in the league.

“When we were midway through the season [in 2016] -- obviously as a rookie, you have a lot going on, from preseason all the way into the postseason -- one of the vets told me, in college, you really just play football, but in the league, you learn football," Simmons said. “ ... It’s things like that that [the veteran players] all know, which makes them so successful on the field instead of just going out there and playing the coverage that’s called. That’s why they’re so successful because of their study of the game. For myself, that’s the level of competitiveness that I want to be at. ... I want to make sure that while T.J or Stew or whoever may be out, that when I’m in there or when Will is in there, they’re not missing a beat with us being in there with them."