49ers DL Armstead week-to-week with hamstring injury

San Francisco 49ers defensive lineman Arik Armstead has been ruled week-to-week with a hamstring injury, the team announced on Tuesday.The 2015 first-round draft pick, 17th overall, has been hampered by injuries the past two seasons, playing in just 14 games with 10 starts.The team has had high hopes for the Oregon product, who has six sacks in 30 career NFL games.”Arik’s going to do a lot of things for us this year,” 49ers defensive line coach Jeff Zgonina told NBC Sports Bay Area in June. “I think he’s more comfortable this year than last year. We tried him at a few spots last year, and I think he’s really starting to feel comfortable at that big end spot and inside pass-rusher on pass downs. I think he has more of a defined role.”Jullian Taylor, a 2018 seventh-round draft pick out of Temple, practiced with the first team on Tuesday in Armstead’s absence.