2012 NFL Mock Draft: Defensive Linemen Who Increased Draft Stock at the Combine

On Monday, the defensive linemen took the field at the 2012 NFL Scouting Combine, and needless to say, it was a good showing by a lot of prospects.

This draft there's quite a bit of versatility along the defensive line, and even after Round 1, there's a lot of solid talent that will benefit defensive fronts.

Therefore, let's take a look at some projected mid-rounders who increased their stock.

Shea McClellin, Boise State

At 6'3", 260 pounds, Boise State's Shea McClellin has the potential to act as a true 4-3 defensive end or potential 3-4 outside linebacker pass-rusher.

In his career with the Broncos, McClellin recorded 19.5 sacks (18.5 from 2009-2011) and 129 tackles. He also intercepted four passes (two in 2011) and forced four fumbles. He's quick off the snap, has a good inside move to complement going outside and is a sure-tackler.

The issue lies within his size to consistently set the edge against the run and take on double-teams, even if one of the blockers is a running back.

At the combine McClellin ran a 4.63 40-yard dash, hit 7.07 seconds on the 3-cone drill and 4.33 seconds on the 20-yard shuttle.

If anything, McClellin simply must build strength and gain weight, but at the same time, keep his quickness and agility. The man knows how to make plays, but won't be too consistent in the NFL without proving to take on bigger lineman and tight ends.

However, he'll at the very least be a mid second-rounder.

Bruce Irvin, West Virginia

If there's one guy who can come into the NFL and make an immediate impact strictly as a pass-rusher, it's West Virginia's Bruce Irvin.

For starters, the man accounted for 22 sacks the past two seasons and forced five fumbles. That kind of production is impressive as he was the main pass-rusher on a rather sound Mountaineers defense.

The downside, however, is that Irvin wasn't much of a rush defender. It comes in a combination of most offenses not running to his size and him playing more as a strict pass-rusher. Not to mention he would see double teams for his presence warranted attention to protect the quarterback.

That said, Irvin had a solid combine with a 4.5-second 40-yard dash, 33.5 inch vertical jump, 10'3" on the broad jump, 6.7 seconds on the 3-cone drill and 4.03 seconds on the 20-yard shuttle.

The man is somewhat undersized at 6'3", 245 pounds, but his quickness and athleticism is second-to-none among defensive linemen. Right now a considered late third/early fourth-round selection, If Irvin can prove his value at defending the run, he'll only increase even more and potentially jump into Round 2.

Chandler Jones, Syracuse

Although Chandler Jones's 2011 season was cut short due to injury, he's still considered a late second/early third-rounder but proved to be better with a strong and consistent performance at the combine.

There, Jones hit 35 inches on the vertical jump, 10 feet on the broad jump and 7.07 seconds on the 3-cone drill. Being that his size comes out to 6'5", 266 pounds, Jones displayed excellent explosion despite not having overly impressive top speed.

Then again, defensive linemen need not have great top speed, although it does help. However, great acceleration and body control matters much more. Concerns only reside when he comes out of his stance too high.

Whether he ends up as a normal 4-3 defensive end or 3-4 pass rushing 'backer, Jones must keep that low center of gravity and learn to have quicker feet. Between 2009 and 2011, Jones recorded 10.5 sacks, forced five fumbles and broke up six passes.

His development will need to emerge at becoming more dynamic off the edge and taking smaller but quicker steps to setup his hands from getting blocked. With great explosion and improved strength, Jones can become an early to mid second-rounder.

Jones' pro day will be most telling as to how fast he can develop into a true defensive end.

Cam Johnson, Virginia

An expected mid third-round draft choice, Virginia's Cam Johnson was the Cavaliers' defensive front leader on a unit that allowed just 343 total yards per game (ranked No. 30 out of 120 schools) and No. 34 against the rush (allowed 128 rush yards per game).

Now, obviously these numbers would be considered poor when compared to NFL defenses, however, Johnson wasn't helped by much other than cornerback Chase Minnifield. With two of Virginia's best defensive players, the Cavaliers had a strong campaign in 2011.

As for Johnson, he continued that momentum unto the combine with a 35-inch vertical jump, 7.2-second 3-cone drill and 4.38 seconds on the 20-yard shuttle. Certainly not the most explosive defensive lineman, but a lot stronger than anticipated.

At 6'3", 270 pounds, Johnson recorded 10 sacks the past two seasons along with five passes broken up. What's impressive about Johnson is that he can set the edge and play contain very well while also being a reliable pass-rusher.

Now, he will struggle against double-teams but still has the ability to force the ball back inside, as well as seal off the cutback lane backside. Provided that he gets a little quicker and learns to attack double-teams, Johnson has a lot of potential.

2012 First-Round NFL Mock Draft

1. Indianapolis Colts: Andrew Luck, QB (Stanford)	17. Cincinnati Bengals (From OAK): Trent Richardson, RB (Alabama)
2. Washington Redskins (From STL): Robert Griffin III, QB (Baylor)	18. San Diego Chargers: Cordy Glenn, OG (Georgia)
3. Minnesota Vikings: Matt Kalil, OT (USC)	19. Chicago Bears: Dwayne Allen, TE (Clemson)
4. Cleveland Browns: Justin Blackmon, WR (Oklahoma State)	20. Tennessee Titans: Alshon Jeffery, WR (South Carolina)
5. Tampa Bay Buccaneers: Morris Claiborne, CB (LSU)	21. Cincinnati Bengals: Mike Adams, OT (Ohio State)
6. St. Louis Rams (From WAS): Riley Reiff, OT (Iowa)	22. Cleveland Browns (From ATL): Courtney Upshaw, LB (Alabama)
7. Jacksonville Jaguars: Michael Floyd, WR (Notre Dame)	23. Detroit Lions: Luke Kuechly, LB (Boston College)
8. Miami Dolphins: David DeCastro, G (Stanford)	24. Pittsburgh Steelers: Kendall Wright, WR (Baylor)
9. Carolina Panthers: Quinton Coples, DE (North Carolina)	25. Denver Broncos: Alfonzo Dennard, CB (Nebraska)
10. Buffalo Bills: Dre Kirkpatrick, CB (Alabama)	26. Houston Texans: Jerel Worthy, DT (Michigan State)
11. Kansas City Chiefs: Nick Perry, DE (USC)	27. New England Patriots (From NO): Whitney Mercilus, DE (Illinois)
12. Seattle Seahawks: Devon Still, DT (Penn State)	28. Green Bay Packers: Zach Brown, LB (North Carolina)
13. Arizona Cardinals: Jonathan Martin, OT (Stanford)	29. Baltimore Ravens: Dont'a Hightower, LB (Alabama)
14. Dallas Cowboys: Janoris Jenkins, CB (Northern Alabama)	30. San Francisco 49ers: Mark Barron, S (Alabama)
15. Philadelphia Eagles: Melvin Ingram, DE (South Carolina)	31. New England Patriots: Stephon Gilmore, CB (South Carolina)
16. New York Jets: Michael Brockers, DT (LSU)	32. New York Giants: Coby Fleener, TE (Stanford)

John Rozum on Twitter.