Racing Positions49ers' contingency plans at safety center on a pair of rookies9YNick WagonerJimmie Ward, George Kittle limited in 49ers practice9YNick WagonerSecondary a concern for 49ers but front seven could balance it out9YNick Wagoner49ers' initial 53-man roster features rookies in prominent depth roles9YNick Wagoner49ers starters put together best preseason performance in loss to Vikings9YNick Wagoner49ers free safety Jimmie Ward close to return with work to do9YNick Wagoner49ers defensive end Aaron Lynch leaves practice with apparent injury9YNick WagonerO-line, backup QB among positions to watch as 49ers open preseason9YNick Wagoner49ers' Ray-Ray Armstrong takes turn with starters at weakside LB9YNick Wagoner49ers' DeForest Buckner leaves practice with apparent ankle injury9YNick Wagoner
