Broncos preview: QB race could shape Denver's season

Training camps are still in the distance, but USA TODAY Sports is providing five things you need to know about every team in the NFL to catch you up on the offseason. Today, the Denver Broncos ...

1. The QB competition is about to ramp up

All eyes are on the quarterback battle between incumbent starter Trevor Siemian and 2016 first-round pick Paxton Lynch. Siemian, who threw for 3,401 yards and 18 touchdowns (with 10 interceptions) in 14 games last season, piloted a passing offense that tied for 21st in the NFL last year. The 6-7, 244-pound Lynch filled in for Siemian twice as a starter last year, but his rookie campaign otherwise amounted to a redshirt year. New coach Vance Joseph has said the quarterback competition won't begin in earnest until training camp.

2. The line received reinforcements, but concerns linger

After repeated struggles up front in 2016, the Broncos loaded up on the offensive line this offseason. Denver signed former Dallas Cowboys guard Ronald Leary and former Oakland Raiders right tackle Menelik Watson, in addition to drafting Utah offensive tackle Garett Bolles in the first round. With Russell Okung's departure to the Los Angeles Chargers leaving a vacancy at left tackle, Bolles or Donald Stephenson will have to step up for the starting role after the unit gave up 40 sacks last season.

MORE COVERAGE:

Broncos' Demaryius Thomas invigorated by Vance Joseph's challenge

C.J. Anderson revitalized by Broncos' offensive change

Trevor Siemian, Paxton Lynch given no easy outs as Broncos' QB race looms

3. An old rival has joined the backfield

Former Kansas City Chiefs running back Jamaal Charles signed with Denver after back-to-back injury-marred seasons. He had surgery on a torn anterior cruciate ligament in 2015 and has struggled to recover, appearing in just five games in the last two years. He will join C.J. Anderson, who’s coming back from knee surgery, as well as Devontae Booker and sixth-round pick De'Angelo Henderson. With Joseph saying he wants to spread carries among different players, Charles could boost the 27th-ranked rushing game if he makes the roster and stays healthy.

4. The receiving corps could soar in 2017

If concerns elsewhere on offense are alleviated, Pro Bowl wide receivers Demaryius Thomas and Emmanuel Sanders should thrive. Both are coming off 1,000-yard seasons, and Joseph challenged Thomas to be a consistently dominant presence this year. Carlos Henderson, Denver’s third-round pick, could become the go-to answer in the slot. Last season at Louisiana Tech, Henderson was named Conference USA’s offensive and special teams players of the year. 

5. The 'No Fly Zone' is still an imposing group for opposing QBs

A potent secondary returns for the Broncos with cornerbacks Aqib Talib, Chris Harris and Bradley Roby, as well as safeties T. J. Ward and Darian Stewart. Denver also drafted Brendan Langley in the third round. It will be a challenge to live up to the performance of last year's No. 1 pass defense, which also allowed an NFL-low 55.4% completion percentage, but new defensive coordinator Joe Woods still has Von Miller to fluster opposing quarterbacks.

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