Dillard (ankle) was placed on injured reserve Thursday.
According to Matt Maiocco of NBC Sports Bay Area, Dillard had offseason ankle surgery and began training camp on the active/PUP list before being activated Monday, but his ankle hasn't responded well to the last few days of practice. The 2019 first-round pick has appeared in 69 regular-season games over his six year career, spending last year in Green Bay. He signed a one-year, $1.17 million contract with San Francisco in May and was expected to be the team's swing tackle behind Trent Williams and Colton McKivitz.