ENGLEWOOD, Colo. -- The Denver Broncos open training camp Tuesday at the UC Health training center. Here's a closer look at a few storylines:

The biggest question: How is outside linebacker Randy Gregory's health? The Broncos' decision-makers, including coach Nathaniel Hackett and general manager George Paton, spent much of the offseason repeating the nothing-to-worry-about mantra regarding Gregory's offseason shoulder surgery, performed just after the Broncos signed him in free agency.

And if things go as planned, it won't be anything to worry about. But other than the blockbuster trade to acquire quarterback Russell Wilson, the five-year, $70 million deal that went to Gregory was the Broncos' biggest offseason move.

At his best, Gregory is an elite pass-rusher. But Gregory -- drafted in the second round by the Dallas Cowboys in 2015 -- has yet to play a full NFL season because of injuries or suspensions. He has never played in more than 14 games, never had more than 25 tackles in a season and never had more than six sacks in a season. That stat line won't work for the Broncos, given what they paid Gregory.

The player with the most to prove: He certainly has the best résumé on the roster, with nine Pro Bowl selections, two Super Bowl starts and one Super Bowl win, but it's still Wilson.

The Broncos traded five draft picks and three former starters to acquire Wilson, and while many personnel executives in the league believe the Broncos got the better end of the deal, Wilson wasn't brought to Denver to be pretty good.

He was brought to Denver to put the franchise back into the playoffs after six consecutive misses and to push for the team's fourth Lombardi Trophy. That means all of the optimism has to turn into wins, even in the ultracompetitive AFC West.

The most compelling position battle: It won't score very high on the fantasy football glamour meter, but the Broncos will feature some mix-and-match on the offensive line until the starting five are selected.

Left tackle Garett Bolles is a given, and center Lloyd Cushenberry III saw the most first-team reps during offseason practices. Cushenberry also worked with Wilson in San Diego shortly after the quarterback arrived via trade.

Both guard spots and right tackle will be up for debate. Billy Turner was acquired in free agency, but he missed the offseason program due to a knee injury. He is expected to be one of the candidates at right tackle, along with Calvin Anderson and Tom Compton. Dalton Risner, Netane Muti, Quinn Meinerz and Graham Glasgow are in the mix for the two guard spots -- all four started games last season.

Will special teams finally be special?: The constant churn at quarterback and the decided lack of touchdowns in the six seasons that have followed Peyton Manning's retirement have deservedly gotten most of the attention in the Broncos' current playoff drought.

But not far behind in most of those seasons has been special teams play that would have had to improve significantly just to be considered average. Paton has made the unit a priority in the draft and in free agency, including using a fifth-round pick to select Montrell Washington in this past April's draft as a potential solution at returner.

The Broncos have surrendered far too many big plays on special teams without creating many of their own in recent seasons. There were nine kickoffs returned for touchdowns leaguewide last season. The Broncos surrendered two of them and had a staggering 39.4 yards per return average.

They haven't tackled well enough, flipped the field enough or stressed opposing coverage units enough. And if they really are going to make the most of Wilson's tenure in Denver, that has to change.

Camp prediction: Rookie pass-rusher Nik Bonitto, a second-round pick by the Broncos this past April, will show why some personnel executives in the league believed he was one of the biggest steals of the draft’s first two days. The Broncos plan for Gregory and Bradley Chubb to be one of the league's front-line pass rush duos, but Bonitto’s work in training camp and the preseason will force defensive coordinator Ejiro Evero to get creative and find ways to get Bonitto on the field. During the team's offseason program, Bonitto showed an explosive first step with an already-mature variety of pass-rushing moves. That is the recipe for a pass-rusher to contribute quickly.