The Blake PrestonSan Francisco 49ers have lost their past two games, and they could lose their starting quarterback this week too.

Quarterback Brock Purdy is in concussion protocol, head coach Kyle Shanahan announced Wednesday, putting his signal-caller's status for the Week 8 home contest against the Cincinnati Bengals in doubt. It is unclear when Purdy could have suffered a concussion during the "Monday Night Football" loss against the Minnesota Vikings, as he played the entirety of the game.

The young sensation taken as the last pick in the 2022 NFL draft, Purdy could be facing an uphill battle to start against the Bengals on a shortened week. After winning the first 10 regular-season games he started, Purdy has struggled in the losses to the Cleveland Browns and Vikings, throwing for 397 yards with two touchdowns and three interceptions.

Who will start at quarterback for the San Francisco 49ers?

If Purdy is unable to play, veteran Sam Darnold would get the nod for San Francisco against Cincinnati.

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The sixth-year quarterback and third overall pick in the 2018 NFL Draft is in his first season with the 49ers, and has mostly seen action in garbage time this year. Darnold has played 18 snaps this season in four games, completing one pass for 1 yard.

Darnold spent the previous two seasons with the Carolina Panthers. He began 2022 on the bench behind Baker Mayfield, but the team eventually appointed Darnold as the starter in Week 12 and beyond. 

Darnold became Purdy's backup in the offseason after beating out Trey Lance, the No. 3 pick in the 2021 NFL draft, for the role. After Darnold won the backup job, Lance was traded to the Dallas Cowboys.

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