Drew Lock’s first career start, against the Chargers, was an up-and-down performance, as expected in a player’s debut. But there were some clear strengths on display by the rookie that gave the Broncos — and general manager John Elway — optimism for his future with the team.



Lock finished 18-of-28 (64.3 percent) passing for 134 yards (4.8 yards per attempt), two touchdowns and one interception (84.5 passer rating).



Offensive coordinator Rich Scangarello designed a conservative game plan that balanced shotgun and under-center plays with four pistol formations, seven play-action passes, five screens and seven completions to running backs.



There has been some talk of this being too conservative of an offense, but this particular game plan against the Chargers seemed fitting given the circumstances: a rookie quarterback behind two tackles outmatched by elite edge-rushers Melvin Ingram and Joey Bosa.



One possible reason Scangarello...