49ers pre-OTA depth chart preview: Offensive Line

The San Francisco 49ers are less than a week away from their first set of OTAs, which means the eventual training camp depth chart will start to get a little more clarity. I should say, clarity for the team. Given that OTAs involve no tackling, it's as much about the players learning the playbook, and any adjustments to it for the veterans. This is the kind of stuff we can't really know about, and so we're left to sort of half guess at what exactly is going on.

Nonetheless, this is our second of what should be a series of about 13 posts looking at the various positional depth charts. We completed our look at the offensive backfield, with quarterbacks and running backs and fullbacks, and followed up with tight ends and wide receivers. We now move on to the offensive line to close out our look at the offense. We'll continue with the format of offseason changes, what the depth chart might look like, strengths and weaknesses, and wrapping with a look at what it all means.

Offseason changes

The 49ers went into the offseason with most of the current group listed in the depth chart below. The only departure was center Jonathan Goodwin, who currently remains a free agent. The team traded a conditional 7th round pick for offensive tackle Jonathan Martin. They then used their first 3rd round pick on USC center Marcus Martin, and their third 3rd round pick on Clemson guard Brandon Thomas. Following the draft, the 49ers signed New Mexico center Dillon Farrell and Michigan State offensive tackle Fou Fonoti.

Depth chart

LT: Joe Staley, Jonathan Martin, Fou Fonoti
LG: Mike Iupati, Adam Snyder, Brandon Thomas
C: Daniel Kilgore, Marcus Martin, Dillon Farrell
RG: Alex Boone, Joe Looney, Ryan Seymour
RT: Anthony Davis, Luke Marquardt, Carter Bykowski, Al Netter

Strengths

Excluding Daniel Kilgore, the starting guards and tackles have been in the same starting lineup since 2012. Remove Alex Boone, and Joe Staley, Mike Iupati, and Anthony Davis have been starting together since 2010. It's not a huge stretch of time, but Staley, Iupati, Boone, and Davis have started through a string of huge games. They have had their down games here and there, but this is a fairly cohesive unit. Staley is playing as well as most anybody in the league, while Davis and Iupati continue to improve. Iupati had a lot of inconsistencies in 2013, but he also was hampered by injuries.

Most importantly, the addition of Jonathan Martin to compete along the line should be a big help for depth. Adam Snyder has been a serviceable utility player, but the group needs to get younger. Martin and Looney could very well take the backup reins in 2014. That backup group could also be pushed by Luke Marquardt and Carter Bykowski.

Weaknesses

Iupati's injuries are of some concern. He went through a couple injuries, and we have to wait and see if he's fully recovered and if he can get back through the season without the nicks and bruises slowing him down.

The big question mark now is at center. Daniel Kilgore got first team snaps in OTAs last year, and got plenty of preseason playing time, but his regular season time has been limited. He could be fine, he could be replaced by Marcus Martin before too long, who really knows. There is plenty of competition at the center position, but replacing a steady veteran like Jonathan Goodwin is going to raise some questions.

What it all means

OTAs are unlikely to tell us a whole lot about the offensive line competitions. If Martin is getting first team snaps over Kilgore that is obviously worth noting, but 

If Kilgore or Martin is able to step in ably at center, the offensive line should be perfectly fine in 2014. But that's sort of the rub. The 49ers clearly like Kilgore, having given him an extension. However, it is reasonable enough that getting supplanted by Marcus Martin would not throw salary structures entirely out of whack. This will be one of the more fascinating competitions to watch when training camp and the preseason get going.

The 49ers have continued to develop their depth as well. Kilgore vs. Marcus Martin is the big competition, but the backups will be fascinating across the line. Jonathan Martin has only played tackle, but I don't think anybody would be surprised if the 49ers gave him some opportunities at guard as well. They also have offensive tackles Luke Marquardt and Carter Bykowski each entering their second season in the NFL. They'll be in the mix, and it will be interesting to see what a year on the sidelines has taught them.