Top OC, OG prospects for 2015

LSU lineman Vadal Alexander will have a chance to hoist himself to the NFL next year. Crystal LoGiudice/USA TODAY Sports

Soon after the 2014 NFL draft concluded, I released my too-early Big Board for the 2015 NFL draft, a ranking which includes players who will be underclassmen during the 2014 college football season. It goes without saying that these rankings are preliminary, as I have hundreds of hours of evaluation ahead on the 2015 class.

A couple important notes about the rankings below:

• This isn't a straight Top 10 list, because I've split these between seniors and underclassmen. I think it's important to rank seniors alone, as those are the only players I can guarantee will be a part of the 2015 NFL draft process.

• In some instances I've included more than 10 players; if two or three guys are extremely close on my board, I simply tacked on those names.

• For this one, I have a total of 20 players, as I've included players across three position groups.

With those parameters in mind, here's an early look at the top guard and center prospects for 2015.

Top five senior offensive guards

1. Tre' Jackson, Florida State Seminoles

2. A.J. Cann, South Carolina Gamecocks

3. Josue Matias, Florida State Seminoles

4. Laken Tomlinson, Duke Blue Devils

5. Quinton Spain, West Virginia Mountaineers