The 49ers defense was flowing aggressively to its left early in Friday’s practice. So Joe Williams cut back the other way.
The rookie running back accelerated down the line of scrimmage, then turned up the field for one of the biggest gains of the morning session.
“I thought he had his best day (Thursday) and then it seemed like today was better than that,” Kyle Shanahan said after practice. “So I thought he’s put two good practices in a row.”
The 49ers spent a fourth-round pick on Williams in April because he had the two traits — cutting ability and speed — Shanahan and running backs coach Bobby Turner seek in a runner. Those gifts, however, had been slow to materialize in the spring and early in training camp when it appeared as if undrafted Matt Breida was the superior rookie tailback.
Williams seemed to have trouble holding on to the football. Like most rookie running backs, he’s struggled against oncoming linebackers and safeties in one-on-one blitz pickup drills. And most glaring of all: He wasn’t finishing his runs with the gusto the 49ers coaches expect.
That led to a chat with Turner a few days ago. Williams was receptive to it and seems to have shaken off the sluggishness with which he was playing.
“I told (Turner) to keep coaching me, to keep staying on me,” he said Friday. “He’s been a type of positive figure since I came in before the draft, a big reason I’m so happy to be here, to be under his wing.”
Williams also is benefiting from a more stringent training regimen. He was one of several players the 49ers deemed too heavy in the spring. And like fellow running back Carlos Hyde and others, he stuck around Santa Clara in late June and July to train with strength coach Ray Wright.
The result is a little less body fat and a little more quickness.
“It takes time with some of these guys, by no means has he arrived with two good practices,” Shanahan said. “That’s why I try not to jump to too many conclusions after each practice. Especially with the younger guys, they’ve got to learn the speed of the game, how to practice. … Joe had a couple good looks (Thursday), which sometimes that’s what they need to spring a little bit of confidence. We’re always hoping it will click because we know he’s got some ability.”
Foster nicked — The 49ers may have taken a collective gasp Friday when first-round draft pick Reuben Foster fell to the ground after a running play while grasping his lower leg.
It turns out he merely sprained his ankle. Foster soon was on his feet and sat out only one snap before returning to the action.
Friday’s session was a typically busy one for Foster who, with fellow inside linebacker Brock Coyle (ribs) and Donavin Newsom (neck) out, lined up at the middle linebacker spot with the second-team defense.
Foster had an interception during one-on-one pass-coverage drills early in practice. In the team setting, he came up with a fumble recovery after a big hit from cornerback Prince Charles Iworah popped the ball out of Breida’s grasp.
“It’s going be hard to keep him off the field,” general manager John Lynch told the NFL Network Friday when asked about giving Foster more first-team snaps. “But we’re going to make him earn it, too. And Kyle’s very cognizant of that. I think Reuben will appreciate it more if he has to earn it and he’s doing his best to do just that. There’s still some things he needs to clean up — he’s a rookie, the mental errors — but we sure like what he’s bringing.”
Et cetera — With strong-side linebackers Ahmad Brooks (veteran’s day off) and Eli Harold (concussion) out of action Friday, sixth-round draft pick Pita Taumoepenu filled in at the position with the second-team defense. Dekoda Watson worked with the starters.
* The Jets claimed ex-49ers receiver Bruce Ellington off of waivers. Jets offensive coordinator John Morton was San Francisco’s receivers coach when the 49ers drafted Ellington in 2014.
* Defensive end Aaron Lynch had an excused absence Friday after his wife gave birth to their second child.