Kyle Shanahan will “probably” announce backup QB before season opener

49ers head coach Kyle Shanahan is not ready to name his team's No. 2 quarterback behind Brock Purdy. But even when he does, the player in that role could change from week to week. Shanahan said during his Tuesday press conference, via NBCSportsBayArea.com, that he's "probably" going to announce a backup quarterback - either Trey Lance or Sam Darnold - before the team's season opener against the Steelers. But that announcement won't happen before San Francisco plays its preseason finale against the Chargers on Friday. Shanahan also said the backup role could "definitely" change from week to week. Plus, via David Lombardi of TheAtheltic.com, Shanahan noted that San Francisco's scout-team QB could change from week to week depending on the opposing quarterback's skillset. That indicates the 49ers are planning to keep Purdy, Lance, and Darnold on the 53-man roster. After Tuesday and Wednesday's practices, Shanahan will figure out the playing time and order for Darnold and Lance. "Today's a big part of that - and tomorrow," Shanahan said. "But we'll decide after these two practices." Lance has completed 22-of-33 passes for 285 yards with two touchdowns and an interception in the...