The 49ers have stocked-up at a few notable positions this offseason. Positions that everyone has been saying needed depth or upgrades. Mostly, they added wide receivers and defensive backs...two of the spots that have historically been the weakest.

I started thinking today though how there are other positions that are not quite as deep. Sure, there may be guys who have that position next to their names, and are backups at the moment...but what do we know about these guys? Have we seen anything from them that suggest the level of play wouldn't drop-off if they were called-upon?

The main position that scares me is center. Jonathan Goodwin finished the season well last year, but started it on shaky ground. We saw some close games, many of which featured very few rushing or passing yards and had to rely on the defense and field-goals to win the game (of course, that was our blueprint last year, it seemed).

But what really frightens me is if Goodwin goes down. Right now we only have a bunch of guys who are supposed to be able to play center, or who are "slotted" to play center...even if they haven't played it before or it was a very long time since they last did.

So what's the position that scares you the most from a depth perspctive?