What concerns you the most heading into OTAs and training camp?

The San Francisco 49ers generally appear to be in great shape heading into the second half of the offseason workout program. The team made a big addition with the trade for Stevie Johnson, they seemingly found their nickel back of the near future in Jimmie Ward, and they added some quality depth across the line. It's easy to be excited about where the team is headed in 2014 and beyond.

However, before we get too far ahead of ourselves, it can occasionally be helpful to look at where the team has weaknesses, or at least, where there might be some question marks. We'll be breaking down the depth chart and the entire 90-man roster over the next two months leading up to training camp, and each will include some discussion of where the team can improve.

For now though, I figured I would see what each of you thinks is the area of most concern for the 49ers. Or maybe just what areas have questions that you'll be pondering heading into the season.

For me, center is an area that is not so much of concern as curiosity. Daniel Kilgore and Marcus Martin will be competing for the role, but my concern is mostly just how either will look in replacing Jonathan Goodwin. While Goodwin was not some monster on the line, it always felt like he settled down what was already a talented line. His veteran presence just seemed steadying for some reason. It's possible it's easier to conclude this given the overall play of the line, but his presence never left us wondering what the heck might happen out there. Kilgore got first team snaps in last year's OTAs when Goodwin stayed home, but it's about seeing Kilgore (or Martin) out there in real game action. Real, regular season game action.

The other area of concern for me is the secondary. I think the team has some very talented players out there, but there are still question marks. Chris Culliver in particular is a guy who raises questions given his injury last year. He was sidelined with an ACL tear, and all indications are that his recovery is coming along just fine. But until we see him back in action, it remains a question mark.

I'd say one final area of "concern" would be at running back. The team has a lot of depth, but a lot of question marks. I think Frank Gore has one more solid year in him, but what do we really know at this point?

Where do you sit in terms of what has you at least a little concerned at this point in the offseason? I think we all can be confident about this team while still maintaining some reservations. What are yours?