We are still a couple of months off from the NFL Draft, but it's never too early to start researching those individual defensive players to get your big board set for your rookie drafts. Let's start by looking at some of the guys who fill the trenches. In no particular order, here are a handful of defensive linemen 

Mason Graham, Michigan

Graham is a big dude, checking in at 6-foot-3 and 318 pounds, but you wouldn't know it from how effortlessly he seems to float around the field. His footwork is impeccable, and he has shown the ability to help stop the opposing run game and rush the passer. His best fit is as a 3-technique. However, he has moved along the Wolverine line, so there's no real risk of him going somewhere he can't fit and thrive. He may not have the overall length or bulk of Quinnen Williams, but the two compare favorably. Graham will be a game-wrecker for whatever team grabs him this April.

Deone Walker, Kentucky

Speaking of big, here's another behemoth of a man. Walker checks in three inches taller than Graham and nearly 20 pounds heavier. Walker may not have the flexibility that Graham has, but will be an adept run-stuffer and has good bull-rush moves to get to the quarterback. Walker blends size and agility and will - like Graham - be a disruptive force in the middle of an NFL line. A good NFL comp is Gervon Dexter Sr, an impressive youngster for the Chicago Bears this past season.

Kenneth Grant, Michigan

It turns out that two of the better defensive linemen in this draft hail from the University of Michigan. Like his Wolverine running mate, he's a big dude who offers some pretty light feet and brute strength. That's about where the comparison ends, though, as Grant is not much of a pass rusher. He will get the occasional sack in the NFL, but his fantasy worth will be through his ability to plug up the middle and stop running backs.  Grant may be drafted as a nose tackle, severely limiting his fantasy potential.  That said, if you're in a league that breaks apart the defensive line position, he may be someone to look at later in drafts since he is definitely a physical freak.

Tyleik Williams, Ohio State

Williams blends size, power, and speed like the rest on this list but tends to disappear occasionally. He has a ton of potential, though, and in the right system, he could flourish. He's an adept run-stuffer who can put pressure on the pocket as well. If he adds some pass-rush moves, he could really jump up as a solid prospect.