Whether an NFL team primarily operates a 4-3 or 3-4 defensive scheme (first number corresponding to linemen, the second to linebackers), the stability and consistency of that unit begins along the defensive line. They are the proverbial tip of the sword, responsible for creating pressure in both the run and pass dimensions. Different alignments and philosophies will ask of varying responsibilities from certain positions, some of which will be alluded to in the below player descriptions.
But regardless of form or flavor, an elite defensive line can wreak havoc in the backfield, free up its own linebackers to fly around and make impact plays and even bail out a lesser secondary by shortening the quarterback's time to throw.
Fletcher Cox, DL, Mississippi State University, junior, DOB: 12/13/1990...Cox is currently, and may remain even, an upset pick as the top defensive lineman in this class. I see him being of equal appeal to odd- or even-front schemes. As a three-technique defensive tackle in a 4-3, his penetration and disruptive style could make him a force inside. Or in a 3-4 alignment, manning a five-technique defensive end spot, he could be a rare playmaker due to his quickness and awareness at the point of attack.
Michael Brockers, DL, Louisiana State University, redshirt sophomore, DOB: 12/21/1990...Brockers is another scheme-versatile defensive line projection. He is expected to measure in this week at the combine around 6'6" and 300 pounds, arguably the most physically gifted in the group. The natural athleticism and rare length do bear great promise but there are also concerns over how unproductive he was the last two years at LSU.
Melvin Ingram, DE, University of South Carolina, 6'2" 275, redshirt senior, DOB: 4/26/1989...I have Ingram listed here as an end with the defensive line grouping but one of his most appealing traits is projected versatility. There is an accepted school of thought that Ingram can play on his feet as a 3-4 outside linebacker and even slide inside to tackle on certain pass rush downs to accommodate other perimeter personnel.
Whitney Mercilus, DE, University of Illinois, redshirt junior, DOB: 7/21/1990...Mercilus is not seen universally as a first-round certainty, though that may change in a few days when NFL personnel get their first up close and personal look at his physicality and speed. He fits into the one-year wonder category after coming from total obscurity to lead the nation in sacks and forced fumbles in 2011. There is also talk that he could be another edge player that can convert to 3-4 OLB.
Dontari Poe, NT/DT, University of Memphis, junior, DOB: 8/18/1990...Yet another underclassman that will finally be officially measured this week in Indianapolis, Poe's dimensions (expected at over 6'3" and around 350 lbs.) and quick feet are a rare combination. And 3-4 teams looking for an impact nose tackle could be very interested.
Quinton Coples, DE, University of North Carolina, 6'6" 280, senior, DOB: 6/22/1990...Coples is widely considered the top 4-3 defensive end prospect in the draft due to his prototypical build and burst. But after a quiet senior campaign, there are questions surrounding his motor, dedication and want-to.
Devon Still, DT, Penn State University, redshirt senior, DOB: 7/11/1989...I like Still as one of the top interior defensive linemen in this class as a three-technique 4-3 DT. He is huge and quick and, while he may never be an elite pass-rusher inside, he generates consistent pressure up the middle. Some question does exist about the consistency of his motor.
Further signaling the importance of talent and future productivity in this unit, along with the depth in the 2012 class, five other prospects have the potential to be first-round defensive line selections.
Jerel Worthy, DT, Michigan State University, redshirt junior, DOB: 4/28/1990
Chandler Jones, DE, Syracuse University, redshirt junior, DOB: 2/27/1990
Andre Branch, DE, Clemson University, 6'5" 260, redshirt senior, DOB: 7/14/1989
Alameda Ta'amu, NT/DT, University of Washington, 6'2.5" 340, senior, DOB: 8/23/1990
Brandon Thompson, DT, Clemson University, 6'2" 310, senior, DOB: 10/19/1989