SANTA CLARA Defensive coordinator Vic Fangio expects Aldon Smith to play at least "some" on Sunday against the Carolina Panthers and said Smith's snap count will depend on nothing but his conditioning.
The 49ers outside linebacker missed six weeks while he was at an out-of-state substance-abuse treatment facility. He played 95 percent of the team's defensive snaps in the first three games this season.
"After a six-week layoff, he may not be back conditioning-wise," Fangio said Thursday. "Every game takes on its own personality how many plays you're playing, how many plays you're playing in a row, how many plays you're playing in different packages. This will be a fluid situation."
Fangio, who watched Smith on Wednesday go through his first full practice since returning to the team, said he looked "a little rusty, obviously."
But he also said it shouldn't take the 24-year-old Smith long to get back to playing form.
"It's not like the guy has an injury to overcome," Fangio said. "He just has to overcome inactivity."
Asked if he was comfortable with Smith playing, Fangio said, "Yeah, absolutely." He added that Smith wasn't getting all the practice snaps at right outside linebacker "because you've got to get everybody ready." He presumably meant Dan Skuta and Corey Lemonier, who filled in for Smith over the past five games, also will get practice repetitions with the first team.
Fangio was more noncommittal about whether two newcomers to the defense, rookie defensive end Tank Carradine and cornerback Eric Wright, would play against Carolina. He said he hasn't decided on either one.
Happy returns Tailback LaMichael James, who has been a healthy scratch the past three games, said he hasn't been given any notification he'll take over punt-return duties for Kyle Williams. But he's preparing as if that will be the case.
"Most definitely got to have that approach to that game," said James, who added he's been taking more punt-return repetitions during practice this week. "Even after practice. Just seeing the ball and, you know, trying to improve."
Coach Jim Harbaugh has hinted recently about a bigger role or any role at all for James, a second-round draft pick last year.
A natural spot seems to be on returns, where Williams struggled against the Jaguars on Oct. 27 in London. Williams fumbled once on a kickoff he recovered the loose ball and misjudged two other opportunities.
Williams has not committed a turnover this season but hasn't added much pop, either. He leads the league in fair catches.
James struggled as a punt returner in the 2012 preseason. He handled that job for one season at Oregon but admitted he "freestyled it" in college, never thinking about the wind or studying the opposing punter.
He also made his NFL punt-catching debut in August at Candlestick Park which, counter-intuitively for most of the country, is windier in the summer than it is in October and November.
"No one really told me that the wind was like that," he said. "So I had a rude awakening."
That awakening, however, forced James to improve as a returner, and he was noticeably better this past preseason.
"It was a challenge for me. I'm not going to sit here and lie about it," he said. "I practiced each and every day."
Injuries Linebacker Ahmad Brooks (stinger) was out of the blue, no-contact jersey he wore in Wednesday's practice. The only player on the active roster who did not practice was rookie wide receiver Quinton Patton (foot).