Jim Harbaugh loses first assistant coach in time with 49ers

The 49ers are going to lose a “trusted agent,” one of Jim Harbaugh’s long-time assistants. But it’s not one of his coordinators leaving for a head coaching gig, at least not yet. According to Matt Maiocco of CSNBayArea.com, assistant offensive line coach Tim Drevno will leave the team after the season to take a job…