Mitchell missed practice on Wednesday and will need to practice in some fashion on Friday to avoid missing Sunday's contest against the Green Bay Packers. The 49ers signed Jacques Patrick to the 53 man roster and Chris Thompson to the practice squad. Trey Sermon practiced on a limited basis on Wednesday, so he appears to have cleared the league's concussion protocol. If this is the case, he will likely be the Week 3 starter if Mitchell cannot go. Mitchell is currently our 19th ranked running back for Week 3 as Kyle Shanahan has expressed optimism that Mitchell would be able to go on Sunday despite the shoulder injury being more severe than initially hoped. Sermon, Patrick, and Trenton Cannon are currently the only healthy backs on the 49ers roster.