Coming into this offseason, the San Francisco 49ers' offensive line was one of the few aspects of the team that were for sure going to be in transition heading into next year. Obviously, a lot changed throughout the course of this offseason and there are now serious red flags all over the team, but that doesn't mean the issues at center and left guard aren't significant.
Well -- there are other issues as well, like Alex Boone being abysmal for much of the 2014-15 season, but provided he gets things back on track, left guard and center are the primary issues.