SANTA CLARA -- Outside linebacker Aldon Smith will play a lot more on Sunday against the New Orleans Saints.
Defensive lineman Ray McDonald might not play at all due to a high-ankle sprain.
[RELATED: Injury report: Davis, Reid limited in return]
And safety Eric Reid is continuing to go through the NFL’s protocol on concussions that will determine his availability for Sunday’s game.
Defensive coordinator Vic Fangio faces a lot of challenges against the league’s second-ranked offense. And there are plenty of moving parts to manage in his own sixth-ranked defense.
Smith played just 12 snaps in the 49ers’ 10-9 loss to the Carolina Panthers last week in his first game back after missing five games while on a voluntary leave of absence for treatment of substance abuse.
On Sunday, the 49ers will need to generate a steady pass rush against the Saints, who throw the ball more than 60 percent of the time.
“We’re trying to get a nice progressive buildup for him that he comes back and plays more and more,” Fangio said. “He would’ve played more last week if the game had been a little different. We weren’t in sub very much.”
McDonald does not appear as if he will be available for Sunday’s game. The 49ers will likely enter the game with Demarcus Dobbs and Tony Jerod-Eddie splitting the action as McDonald’s replacement.
Rookie Tank Carradine, who has yet to play in an NFL game, is an option as an inside pass-rusher. When asked if Carradine is ready to play, Fangio answered, “I don’t know the answer to that.”
Reid practiced Thursday for a second day in a row with a no-contract blue jersey. Reid, who has sustained two concussions in his first nine games, appears to be on pace to play Sunday.
“The chances are good for that but that’s up the protocol he has to go through,” Fangio said.
Veteran Eric Wright will see his first playing time since signing with the 49ers in August. Wright, was activated last week from the non-football illness list, takes the job as the team’s sixth defensive back that was previously held by Perrish Cox. The 49ers waived Cox on Tuesday to open the way to get Wright involved.