Why Joshua Dobbs was chosen as 49ers new starting QB

It looks like the San Francisco 49ers won’t have quarterback Brock Purdy for their season finale against the Arizona Cardinals on Sunday.

Week 18 will mark the second game Purdy has missed this season, but this time the starter in his stead will be different. Head coach Kyle Shanahan on Wednesday announced Joshua Dobbs would get the start ahead of Brandon Allen, who has been Purdy’s backup for virtually the entire season.

According to Shanahan, the change from Allen to Dobbs has more to do with the personnel surrounding the QBs than either player’s performance. He confirmed the switch was because San Francisco is down so many offensive lineman, and Dobbs’ mobility gives the 49ers offense a better chance to be successful. Dobbs has 503 rushing yards and seven career rushing touchdowns, including a seven-yard TD scamper in Monday night’s loss to the Detroit Lions. Allen has 68 yards on 36 carries in his career.

Shanahan heaped praise on both signal callers though, giving an indication that one or both may be back in 2025.

“(Dobbs has) been great, him and Brandon,” said Shanahan. “They’ve been two good guys to have there. I’ve kind of looked at both of them as our two throughout the year. Kind of a little bit what I said in preseason. But they both have done really good looks on scout team, they split all the reps there. They’re always ready. They both prepare like they’re going to be a starter every week, so they’ve been great.”

If the 49ers can’t retain both Allen and Dobbs when they hit free agency in the offseason, Dobbs’ performance Sunday may determine how much San Francisco prioritizes bringing him back.

Undrafted rookie Tanner Mordecai is another other option if the 49ers don’t bring back one or both of Allen and Dobbs. While he wasn’t in the mix to be the starter Sunday because he hasn’t gotten enough reps behind the other two QBs, Shanahan said Mordecai has found other ways to make the most of his first NFL season.

“It’s always tough having four, just because of the reps,” said Shanahan. “So I mean, that’s kind of, (Minnesota Vikings QB) Nick Mullens his first year, I think he was the fourth and he got scout-team reps at safety until basically his first start. So that does happen. You’ve got to find ways to get the work in, but he’s taken advantage of his time here too.”

Dobbs performed well in his handful of snaps in Monday night’s loss after Purdy went down with a right elbow injury. If he puts together another strong outing behind a patchwork offensive line, he may quickly become San Francisco’s second-biggest offseason priority at QB behind Purdy and his contract extension.