Mullens is starting, but for how long?

Daily 49ers blog for NBC Bay Area website: Nick Mullens is now the 49ers' starting QB, but Kyle Shanahan says C.J. Beathard's story isn't over yet. https://www.nbcbayarea.com/news/local/Mullens-Not-Set-in-Stone-as-49ers-Starting-QB-500145831.html