SANTA CLARA -- Ian Williams practiced Wednesday for the first time since he suffered a broken left ankle last season.
Williams' return comes at a time when the 49ers are in need of a replacement for veteran nose tackle Glenn Dorsey, who suffered a torn biceps earlier in camp and is sidelined indefinitely.
"Our last look at Ian was last camp and into the second game," 49ers defensive coordinator Vic Fangio said.
Hence, Fangio and others in the 49ers organization are eager to see how well Williams has recovered from an injury that required four surgeries.
Williams participated in the team's morning walk-through and the full-scale practice in the afternoon. Fellow defensive tackle Ray McDonald said he was impressed by what he saw.
"From the standpoint of individual drills and technique-wise, he looked really good," McDonald said.
Williams said it's going to take some time before he can get a strong feel for where he's at in his near-year-long recovery.
"It's different running around, cutting, everything like that; that's the easy part," Williams said. "Anybody can do combine drills like that. But when you're pushing against somebody that's 350 pounds, that's totally different than just running the 40 (-yard dash). I'm excited just to get back out there and just see how it feels."
The 49ers received a slew of other good news Wednesday. McDonald and defensive tackle Justin Smith practiced for the first time in awhile. In Smith's case, it marked his first appearance since training camp started.
Wide receivers Michael Crabtree and Brandon Lloyd, cornerbacks Chris Culliver and Tramaine Brock, tight end Vance McDonald and running back LaMichael James (elbow) also returned after absences of varying lengths.
As for Williams, Fangio said he intends to ease in Williams, ever mindful that Williams last participated in full-team activities Sept. 15, 2013.
"He's cleared to practice," Fangio said. "The usual protocol is that they go through individual drills, see how they feel. If things are going good, they can progress and do more. If not, we'll back off and then gradually get him into team drills."
The nose tackle plays approximately 40 percent of the time in Fangio's 3-4 scheme.
Smith and McDonald are the projected starters at tackle. Dorsey, Williams, Demarcus Dobbs, Tony Jerod-Eddie and Quinton Dial are the backups.
With Dorsey out of the equation, perhaps for the entire season, there's a sizable void. Suddenly, Williams has the potential to become an integral part of the defensive line once again.
"I'm not going to lie to you," Williams said. "Yeah, it's pressure. It's the NFL. So, there's pressure every day. But this is what we do. We're built to withstand that pressure. They put us through workouts to break through that pressure."
Williams suffered his injury on the third snap of his first-ever start for the 49ers, when Seattle Seahawks right guard J.R. Sweezy cut-block Williams. Dorsey replaced Williams and played well the rest of the season.
Williams, who turns 25 on Aug. 31, now has a chance to regain a starting job. His playing experience his first three seasons consisted of six games.
"There's not a lot of regular-season snaps" to go off, Fangio said. "Last training camp and preseason, he was playing well for us. We'll see how close he is back to that form."
Wilson, 27, played in 15 games in his first three NFL seasons, one each with the San Diego Chargers, Carolina Panthers and Pittsburgh Steelers. Both his starts came last season for the Steelers.
Lynch missed practice time earlier this summer with a hamstring strain. He played only nine snaps on special teams against the Baltimore Ravens last Thursday.
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