The San Francisco 49ers have typically carried four running backs and a fullback on their 53-man roster. They've traded two RBs for fifth-round draft picks in the past, Matt Breida and Jeff Wilson Jr., during Kyle Shanahan's tenure as head coach. If Elijah Mitchell can fetch a return, then perhaps the 49ers have adequate depth to orchestrate another trade. San Francisco has been happy with Cody Schrader and Patrick Taylor Jr., so expect at least one of those backs to remain in the ...