It was welcomed news for a team that allowed 237 rushing yards in a 20-point loss in Baltimore to open the preseason less than a week ago. For the first time this camp, the team's presumed starting trio along the defensive line took part in practice.
And it was a physical one at that.
The 49ers spent much of the afternoon working in full-team drills with pads. There wasn't much of a grace period for the three linemen. They participated in full and received the lion's share of reps with the first team. Smith had been out of practice while recovering from offseason shoulder surgery, while McDonald had been dealing with an apparent leg injury.
Given the veterans' familiarity with the defense, it didn't appear the 49ers were in any rush to get them back on the field during the first two weeks of camp.
But it was an especially noteworthy day for Williams, who is coming off four surgeries to repair a broken ankle suffered in Week 2 of last season against Seattle. His healing process required four surgeries, with the most recent coming in February to remove a plate stabilizing the ankle.
Hours before practice, Williams said he was unsure of how his surgically repaired ankle would respond to real football activity after spending the first two weeks of training camp doing conditioning drills. He was activated off the physically unable to perform list earlier Wednesday.
"I don’t think I’m clear of that final hurdle yet," Williams said. "I’m still working every day just to get better - push myself to see how far I can go and better myself.
"When they activate you off PUP ... that’s the paper hurdle. You still got to get over that mental hurdle."
Defensive coordinator Vic Fangio didn't sound like he was expecting Williams to return to full speed as quickly as he did.
"The usual protocol is that they go through individual (drills), see how they feel," said Fangio before practice. "If things are going good they can progress and do more. If not, we’ll back off and gradually get them into team drills.”
With Glenn Dorsey likely out for the season after sustaining a torn biceps tendon earlier in camp, Williams becomes a key figure on the defensive front. Entering 2013, the Notre Dame alum won the job at starting nose tackle before giving way to Dorsey after suffering his ankle injury early in September's loss in Seattle.
"There’s not a lot of regular season snaps. But last training camp and preseason, he was playing well for us and we’ll see how close he is back to that form,” Fangio said.
The three linemen weren't the only key figures to return to action.
Michael Crabtree was back on the field for individual drills for the first time since the first week of camp, but did not participate in the team session.
Tramaine Brock was also back for the first time since spraining an ankle during the first week of camp. But he didn't participate in team drills either. Chris Culliver practiced, continuing his trend of on-again, off-again participation while he returns from his ACL tear that cost him all of last season. He was active during the first half of full-team drills.
LaMichael James was back, donning a blue non-contact jersey with a heavy brace on his right arm. It was the first practice James participated in since dislocating his elbow during a blitz pickup drill during the first weekend of training camp. He worked with both special teams and the offense. Vance McDonald, who hadn't practiced since Thursday's game, was also back wearing a blue jersey. His injury has not been specified.
Rookie sixth-round pick Kenneth Acker had two interceptions on the day. The first came via Blaine Gabbert on a throw out left intended for Bruce Ellington. He picked off McLeod Bethel-Thompson on a pass to David Reed over the middle for his second.
It had been a relatively nondescript camp for Acker who has gotten the majority of his reps with the third team to this point. But with Culliver sitting during the final half of practice and Cook's injury, he received first-team reps on the right side opposite fellow rookie Dontae Johnson.
Cox made a nice play on a deep pass from Colin Kaepernick to Quinton Patton in the end zone during a two-minute drill. Cox made the catch over Patton and appeared to get both feet in bounds. It would have been Cox' fourth interception of Kaepernick this camp, but it was ruled out of bounds.
The 49ers had a "live" goal line drill, meaning full contact that included tackling midway through the practice. Only reserves participated, but it was a rare occurrence since Jim Harbaugh took over as coach.
Even in fully padded practices, San Francisco has not allowed much physicality to this point in training camp out of fear of injury to key players, and rightfully so given the way things have gone.
On the session's first play, Jewel Hampton broke through over right guard for a touchdown. It looked as though the defense was still unclear about whether or not they were allowed to tackle the ball carrier, if D-line coach Jim Tomsula's animated reaction was any indication.
The drill was likely geared more towards the defense, with Hampton and reserve backs Alfonso Smith and Glenn Winston getting carries behind the backup offensive line.
Patrick Willis had the day off and doesn't appear to be dealing with an injury. Fangio said during his media session the battle at inside linebacker to replace NaVorro Bowman was "very even." So it's likely Willis' day off was to allow Chris Borland and Michael Wilhoite to get more reps.
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