SANTA CLARA — Defensive tackle Arik Armstead, whose 49ers career has been hindered by injuries, is being sidelined by a hamstring issue only four practices into training camp.
Armstead, the team’s top draft pick in 2015, had fared well as camp began with him shifting to a new role as the “big end” on the defensive line.
He is listed as “week to week,” as is second-year tight end Cole Hikutini, who won’t practice this week, according to the team.
Armstead has missed 18 of the past 32 games, having dealt with a shoulder injury in 2016 and a fractured hand last season.