San Francisco Giants backup catcher Tom Murphy will get an injection for a herniated disk in his back that will sideline him for at least two weeks. It could keep him from being ready for the start of the season. Giants manager Bob Melvin said Monday that Murphy will have a couple of weeks of inactivity and then will have to build back up after that. Murphy is going into the second season of a two-year, $8.25 million contract with the Giants. He played in only 13 games last year before a season-ending knee injury in May.