San Francisco 49ers over/under: How many offensive linemen will start games in 2015-16?

The San Francisco 49ers have fielded some of the best offensive lines in the league over the past few seasons, 2014-15 notwithstanding. Guys who were incredible in 2013, like Alex Boone and Mike Iupati, struggled big time in 2014 and the 49ers went from having some of the best blocking in the league to some of the worst.

There are those who would like to place all the blame on Jonathan Martin, despite the fact that Iupati was considerably worse than him at times, and the fact that Boone was downright abysmal over the first several weeks of the season. Both players did get better as the season went on (Martin did not), granted, but it was all a big mess. There were also some significant injury concerns, with Daniel Kilgore going down and injuries to both Iupati and right tackle Anthony Davis.

It was ... a bad situation all around. Going forward, the 49ers have some significant concerns, but there's also to like about the offensive line. Joe Staley is healthy, Davis played at a high level at times last season and Boone will hopefully be attending training camp in shape and ready to roll from the onset. Those are all positives, but the left guard and center positions are still up in the air.

Iupati, for all his struggles, was one of the best run-blockers in the league and it's unclear who will take over at left guard. At center, Kilgore is coming off an injury and Marcus Martin was only average in his playing time. Joe Looney and second-year player Brandon Thomas are in the discussion at the left guard spot. Now, I'll say that Kilgore was excellent when starting but who knows how he'll look coming off injury?

I like enough of what I saw from Martin to believe that center might just be a positive next season. But left guard scares me, with Thomas spending his rookie season on injured reserve and Looney not really standing out in his given playing time. I'm not convinced one of those guys will take the job and run away with it. And any time a team has to shuffle the line during the season, the worse off that line typically is.

Consistency is key for a strong offensive line and I'm not entirely sure that's possible heading into next season. So this time we'll do an over/under that's a little different. How many players do you think will wind up starting a game on the offensive line? I'm going to do the obvious thing and set the over/under at six players, but I ultimately think even without injuries playing a part, there's room for at least eight guys starting games next season.