49ers to lean on Mykel Williams, Alfred Collins amid overhaul

It started with Collins, who was merely an observer due to a minor calf issue, watching Williams, West, and undrafted 301-pound tackle Sebastian Valdez go through warmups. There was considerably more size on the D-line portion of the field than at any 49ers’ minicamp in recent memory, and that served as visual confirmation of the team’s massive reinvestment in that position group via the recent draft.