Top 5 takeaways from 49ers joint practice with Broncos

San Francisco 49ers quarterback Jimmy Garoppolo throws a pass during a combined NFL football training camp with the Denver Broncos at the Broncos’ headquarters Friday, Aug. 16, 2019, in Englewood, Colo. (AP Photo/David Zalubowski)ENGLEWOOD, Colo. — A mostly civil practice unfolded on the Denver Broncos practice Thursday as the 49ers came for their first visit since 2016. Here are the top takeaways from the two-hour session:

Offensive line concerns

An injury-riddled training camp has another apparent casualty: Mike Person, the starting right guard. After participating throughout practice, emerged from the 49ers locker room on crutches with an orthopedic boot on his left foot, and he was driven…