If Brock Purdy doesn't play against the Green Bay Packers on Sunday, the 49ers have a backup plan in place for the pivotal NFC showdown at Lambeau Field.
General manager John Lynch detailed that plan on his weekly KNBR "Murph & Markus" appearance Friday.
"Brandon Allen and Josh Dobbs would both be ready, but Brandon would get the first snaps."
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Purdy has been a limited participant in practice this week as he continues to deal with a shoulder injury he sustained during San Francisco's final-second loss to the Seattle Seahawks on Sunday.
"It was somewhere during that Seattle game, I'm not sure if Brock knows [when he injured it]," Lynch said. "He kind of fought through it throughout the course of the game, but I think he was so focused on trying to win that game. We had a plan to try and quiet that down. Wednesday [he] didn't do any throwing. Thursday he started to do some throwing and then went inside and did some rehab per the plan.
"We'll see where he's at today, hopefully, he makes progress and we can have a shot at this weekend, but we'll see."
Lynch also revealed that Purdy had an MRI on his shoulder but didn't disclose any further details.
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The starting quarterback for the upcoming game typically speaks to reporters the Thursday before game day, but since the 49ers don't yet know who that will be, after a better assessment following Friday's practice, the quarterback who comes to the podium Friday is expected to be the starter.
"We feel good about where it's at from that standpoint [after the MRI], but you have to be able to go out and operate," Lynch said. "So we're kind of figuring all that out. Brock's going to show up here today and we'll see where he can go in terms of practice and we'll make some decisions accordingly."
Purdy has started all 10 games for the 49ers this season. He is completing 66 percent of his pass attempts for 2,613 yards with 13 touchdowns and eight interceptions. He also has run the ball 51 times for 267 yards, with a team-leading four touchdowns on the ground. In 16 games last season, he rushed for 144 yards on 39 attempts.
Allen, 32, has made just nine starts in his NFL career. His last start was in the final week of the 2021 season, when he completed 15 of 29 pass attempts for 136 yards with one touchdown and no interceptions for the Cincinnati Bengals in a 21-16 loss to the Cleveland Browns.
Allen beat out Joshua Dobbs for the backup job to open the regular season.