Now that outside linebacker Von Miller is signed, the question of who the Broncos’ quarterback will be returns to center stage. The depth chart, written in pencil by coach Gary Kubiak after watching offseason workouts, has veteran Mark Sanchez holding the coveted No. 1 QB spot.

Second-year quarterback Trevor Siemian has gone from an afterthought to a serious contender to lead the defending Super Bowl champions on the field Sept. 8 against Carolina. Sanchez (72 starts, 2,267 passes) has much more experience than Siemian (one kneel-down), but the latter knows the playbook, and the Broncos’ coaching staff’s wants and needs better. That advantage can’t be understated.

Holding the No. 3 quarterback spot is first-round pick Paxton Lynch. When it comes to talent and potential, Lynch is the leader of the bunch with size, athleticism and arm talent. What Lynch needs most is repetitions, time and coaching to unlock the tools that made the Broncos believe he can be their quarterback of the future. Related Articles Two-tight end personnel may be Broncos’ best approach early in season

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Denver is expected to lean heavily on its defense and running game, so the most important factors to win this job will be consistency, ability to lead and limiting turnovers.

Sanchez: It starts with earning trust for the 2009 fifth pick. His career has been filled with potential, but his production has fallen short as he went from the franchise quarterback in New York to an unwanted backup in Philadelphia. Turnovers always have plagued Sanchez, and often in the most crucial moments. As a starter in New York, his passing accuracy hovered around 55 percent as he threw 68 touchdowns and 69 interceptions. He raised his completion percentage in Philly, but the turnovers remained a problem. Can Kubiak trust Sanchez not to make crucial mistakes?

Siemian: It’s unclear whether the amount of unknown behind the former seventh-round pick helps or hurts his chances to win the job. Siemian might have the strongest arm of the bunch and the most comfort in running Kubiak’s offense. Siemian’s accuracy has improved, but it still isn’t his forte. His in-game NFL experience isn’t much different from Lynch’s. Does Kubiak believe Siemian can lead the team to a win when it counts?

Lynch: Kubiak described the rookie’s offseason work as “up and down,” which isn’t a great sign for throwing mostly in T-shirts and shorts, but not too far off from expectations for Lynch. He spent the majority of his college career in the shotgun, making three-step-drop completions. His talent is undeniable, but the shaky footwork, indecisiveness and lack of NFL experience that are typical of a rookie make it a risky proposition to put him on the field early. Will Kubiak roll the dice on Lynch’s potential if the season starts shaky?