San Francisco 49ers running backs Elijah Mitchell (hamstring), Isaac Guerendo (hamstring) and Patrick Taylor Jr. (undisclosed) have all returned to training camp practices in the last two days. The only Niners running back out of practice still is starter Christian McCaffrey (calf), but he's been doing heavy work on the side. Mitchell will now try to hold off Jordan Mason for the RB2 role in San Fran. Although McCaffrey will end up missing the entire preseason, the 49ers aren't worried ...