ESPN draft guru Mel Kiper Jr. has released his early top-five rankings at each position.
Here are the positions he's looked at so far:
The No. 1 overall tackle prospect is Notre Dame's Louis Nix III.
Johnson, who was third on LSU's team with 10 tackles for loss last season, has just scratched the surface of how good he can be. He only started in three games a year ago, but is freakishly athletic for a 6-foot-3, 304-pound interior lineman. Hence the nickname "Freak."
What stands out about McCullers is his mammoth size. He's 6-8 and 360 pounds and is the ultimate space-eater. The Vols are moving to a 4-3 base defense next season and will be looking for more production out of McCullers, who had 5.5 tackles for loss a year ago in his first season in the SEC after coming over from junior college.
Of note, Kiper had Florida's Dominique Easley listed among the defensive ends. He's played both, but the Gators' plan is to play him inside at tackle next season.
Some of the other draft-eligible defensive tackles from the SEC to keep an eye on this fall:
Ego Ferguson, LSU: He's hovered in the shadows the past couple of seasons, but that's going to happen when you're playing on LSU's defensive line. He'll be front and center next season for the Tigers.
Damien Jacobs, Florida: He's done it in flashes, but should be more consistent in his second season in the SEC after coming over from junior college.
Byran Jones, Arkansas: The 6-2, 310-pound senior tied for sixth on the team last season with 52 total tackles. The Hogs feel good about their entire defensive front in 2013.
Kelcy Quarles, South Carolina: Jadeveon Clowney has plenty of talent around him on that South Carolina defensive line. The 6-4, 298-pound Quarles had eight tackles for loss last season and is extremely athletic for an interior lineman.
Donte Rumph, Kentucky: He had his spring cut short by shoulder surgery, but the 6-3, 323-pound Rumph is an imposing figure in the middle. If he's healthy, look for him to be on a lot of teams' draft boards.