The San Francisco 49ers have finally named Brock Purdy's backup.

After a battle that lasted throughout training camp and the preseason, head coach Kyle Shanahan announced Brandon Allen will be the No. 2 QB for the 49ers. Josh Dobbs will be the emergency third QB.

Given how the two players looked in camp and the preseason there wasn't a surefire choice. Both had their ups and downs, and Dobbs managed to work his way into the conversation by quickly picking up the offense and closing the gap between him and Allen, who spent last season with the 49ers.

It's not a surprise Shanahan went this route with his decision.

If the 49ers don't have Purdy under center, Shanahan will want to remove as many variables as possible from the offense. Allen can run the offense effectively and deliver throws to the right spots.

Dobbs can do that, but he's still learning Shanahan's scheme and his athleticism adds a layer of unknown to his game. He made plays with his legs in the preseason, but he also held onto the ball too long at times and took unnecessary negative plays by trying to extend a play for too long.

It was clear after the preseason that the ceiling was higher with Dobbs, but the floor was higher with Allen. The latter is what matters to the head coach in the event they need to survive a stretch without their starting quarterback.

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This article originally appeared on Niners Wire: 49ers make unsurprising decision with backup quarterback