With Michael Sam's brave decision to come out as gay in the run-up to the 2014 NFL Draft, the media spotlight on him has been bright and focused. In addition to the attention given to his personal life, there has also been an exponential increase in scrutiny of his on-field play. The term ‘tweener' has thusly positioned itself at the vanguard of our NFL Draft lexicon of late, because regardless of Sam's sexual orientation, there were already questions about his role or position on an NFL defense.

Update: Read our NFL Draft scouting reports 2015 for the top prospects.

SI's Doug Farrar wrote that "Sam could be a reasonably effective player in a 4-3 defensive line rotation, or a run-side endbacker in a 3-4, if he improves his technique and finds a way to use more pure power on the field. The [lack of] speed probably is what it is, and that's a problem - because edge-rushers need more than the burst he currently has, and tweeners who move inside require far more ability to move people than he's shown."

Tweener. Defensive end. 4-3 end. Standup linebacker. Run-side endbacker. Edge rusher. 4-3 outside linebacker. Rush end. When studying the draft and learning about potential targets for your team, these are words you're bound to hear a lot this year. What do these terms refer to, what are the differences between them, what makes a "tweener," and what effect does that have on evaluation? That's what I'll try to explore here, but first, a little background on the two main families of defense in the NFL -- the 3-4 and the 4-3 -- is in order.

The 4-3 vs. the 3-4

One could write ten thousand words on the history of and differences between the 4-3 and the 3-4, but for brevity's sake, I'll just give a basic cliff-notes version to set the stage for evaluating draft prospects. As it relates to the 'tweeners' that you'll hear about in the coming months, it's important to note that rush ends -- the 3-4 outside linebackers and the 4-3 defensive ends -- can have somewhat similar body types or athletic traits, but they have divergent on-field responsibilities and the necessary skill-sets and styles vary.

The 3-4 defense

Very generally speaking, because there are 50 shades of grey therein, the teams that run the 3-4 currently include the Niners, Jets, Cardinals, Ravens, Packers, Chiefs, Chargers, Redskins, Browns, Steelers, Eagles, and others.

Here's a general look at a 3-4 defense; shown below is the San Francisco 49ers base personnel. Aldon Smith, at bottom, is the weakside rush outside linebacker. Ahmad Brooks is the runside backer - angled outside on the slot receiver initially, but shown as he starts creeping in prior to the snap, to rush the passer.

Ahmad's creeper action is the perfect example of why the 3-4 is so popular, and is, to me, the reason it's so damn cool. With a versatile outside linebacker stationed on both sides of the defensive formation, each capable of adroitly dropping back into pass coverage or rushing the passer with aplomb, opposing quarterbacks don't know where pressure is coming from or where coverage is going.

"I'm not saying it's better," 3-4 enthusiast Bill Parcells once said, but "here's [the advantage]: At any time, you can drop eight people into coverage, and that complicates things for the quarterback. Not many four-man line teams have the ability to do that."

Or, as former Houston Texans and now Chicago Bears linebackers coach Reggie Herring explained it...

So... yeah, go have fun with that, quarterback guy.

The 3-4 outside linebacker

As for those versatile chess pieces on the edges: there are many names for the 3-4 outside linebacker, but when you picture the prototype for that position, picture Dallas' DeMarcus Ware. San Francisco's Ahmad Brooks & Aldon Smith, Kansas City's Justin Houston and Baltimore's Terrell Suggs, among others, come to mind, but Ware just represents that Platonic ideal.





6'4, 250 pounds. Long arms. Speed. Quickness, agility. Explosiveness. Power. Ware's numbers coming out of Troy back in 2005 were absurd.





Ware ran a 4.56 forty, had a 38.5" vertical jump, ran the three-cone in an incredible 6.85 seconds. His 4.07 short shuttle showcased amazing short area burst, and he posted an impressive 10'02" broad jump, reflecting his explosiveness. He also put up 27 reps on bench, indicating he had strength to go with his speed. Go ahead use those numbers as the bar to compare with rush ends in the upcoming Combine.

3-4 OLB Responsibilities

There are typically slight differences between the weakside outside linebacker (the rush specialist) and the strongside outside linebacker (the run stuffing, pass covering specialist), but for simplicity's sake, let's just talk in general terms.

Outside linebackers in the 3-4 are typically force players - they set the edge for their defense and either make the tackle, hit the quarterback, or move the action back inside to their cohorts. To do this, it typically requires a player with long arms and a powerful core -- able to take a tackle or tight end head on, engage, and stack/shed or control them at the point of attack to turn the play back inside. Endbackers in a 3-4 have to be strong, physical tacklers with good-to-great short area burst to contain running back runs and/or quarterback scrambles.

Outside linebackers in the 3-4 are typically force players

Both 3-4 OLBs should be explosive pass rushers. The best do this with speed, lateral quickness, agility, flexibility, and power. These attributes combine with necessary techniques, whether it be a swim-move, club move, hump move, counter, spin-move, dip, or any combination of the above, to create an effective rusher.

Additionally, 3-4 stand-up linebackers should have the fluidity and spacial awareness to drop back into either man or zone pass-coverage. The ability to keep one's eyes in on the quarterback while dropping to a landmark or finding, recognizing, and disrupting or breaking up a known route combination sets the great/good apart from the average. This ability is often referred to as "instincts."

Easy.

It's no wonder that elite players at this position are typically among the highest paid in the NFL.

The 4-3 defense

Before I overstate the awesomeness of 3-4 linebackers, it's worth noting that the best 4-3 defensive ends are also among the highest paid players in the NFL. I'll get to what they must do to succeed, but first, let's look at the 4-3.

NFL teams that currently run the 4-3 defense (with lots of shades of gray) include the Seahawks, Bengals, Bears, Bucs, Cowboys, Falcons, Rams, Lions, Jaguars, Vikings, Bears, and Panthers, among a few others.

Below, here's Seattle's nickel 4-3 look to counter Denver's three-receiver formation. We see four down linemen with Walter Thurmond the nickelback (replacing one linebacker in the front seven), matched up with Wes Welker.

Cliff Avril is the strongside defensive end here (top), and on the weakside (bottom), you have Chris Clemons, aligned wide in a 9-technique (techniques denote the relation of defensive players to the offensive line).

As with the 3-4, there are typically style and size differences between the strongside (side with the tight end) and weakside defensive ends, but to keep things basic, I'll just describe pass rushing defensive ends.

The 4-3 defensive end

When you think of 4-3 defensive end prototypes, some players that come to mind include, perhaps, Jared Allen, Jason Pierre-Paul, Mario Williams, John Abraham, or Julius Peppers. For me, the new 4-3 DE player prototype is St. Louis' Robert Quinn.





6'4, 265 pounds. Long arms. Power, burst, speed, tenacity. Quinn's numbers coming out of North Carolina back in 2011 were absurd.





Quinn ran a ridiculous 4.62 forty, had a 34" vertical jump, a 7.13 three-cone and a 4.40 short shuttle. He repped out 22 on the bench press, and registered a 9'08" broad jump. At 262 pounds, those are good numbers. After a few seasons, Quinn has put it all together, and is now one of the most dominant, downright scary pass rushers in the NFL.

4-3 defensive responsibilities

Again, there are typically slight differences between the weakside defensive end (the rush specialist) and the strongside defensive end (the run stuffing, edge setting specialist), but for simplicity sake, let's just talk in general terms.

More important is that 4-3 ends almost always must be explosive pass rushers.

Like outside linebackers in the 3-4, defensive ends in the 4-3 are often asked to be edge setters. The job typically requires a player with length - good height, at least 6'3, and long arms, at least 33", and a powerful core -- able to take a tackle or tight end (or sometimes a double team of frontside blocks) head on. 4-3 DEs must have the innate ability to instantaneously discern a run from a pass. If they hesitate to rush the quarterback thinking it might be a run, they've already lost, and if they fly upfield with no concern for the run, they'll become a liability for their defense. When it is a run, they must play physically on the tight end or tackle, stack, shed, and force things inside.

More important is that 4-3 ends almost always must be explosive pass rushers. An explosive, quick-twitch first step is integral, almost above all else. That first-step, while key, must be combined with a complement of moves - disengagement techniques, such as the swim-move, club move, hump move, counter, spin-move, dip, or any combination of the above.

When dealing with NFL Draft prospects, you'll hear scouts talk about a pass rusher's ability to convert "speed-to-power." Watch Cliff Avril on your right below demonstrate that idea. This was a key, game-changing play in the biggest game of the year. This is what scouts will be looking for.

Tweeners

The fight against perception:

Of course, not everyone can be 6'3/6'4, 250-260 pounds with 4.5 speed and elite quickness and power. Some players can have some of those athletic attributes but come in a touch short, or a touch light. These are often the tweeners you hear about. Some of these so-called tweeners buck NFL trends and become dominant at their positions - Terrell Suggs was considered too slow when he ran in the 4.8s at the combine. I think he's doing ok for himself. Robert Mathis led the NFL in sacks this year with 19.5, and he's only 6'2, once considered too short for a defensive end or outside linebacker.

Despite those success stories, for every Dwight Freeney (6'1), Charles Johnson (6'2), and Terrell Suggs (slow as shit), there are scores of tweeners that never found success in the NFL. That said, there is hope for the height/weight impaired. Why? Because ...

It's a hybrid front, sub-package-heavy world

Teams like the Niners, Patriots, Dolphins, Colts -- hell, probably every team -- use concepts and looks from both the 3-4 and the 4-3. Pete Carroll, who's been running a 4-3 Under defense since before I was born, recently conceded that the Seahawks run a 4-3 defense with 3-4 personnel. The Patriots mix one-gapping 4-3 principles with two-gapping 3-4 principles... at the same time. Furthermore, teams employ sub-package personnel groupings so often there's almost no such thing as base personnel or even starters anymore.

The long of the short of it is, there are opportunities for specialized players these days. Take the Seahawks' front seven: the player to log the most amount of snaps on the year was DT/DE Michael Bennett, who topped out at 57 percent of Seattle's total defensive snaps. He was followed by DE Chris Clemons (54 percent), Cliff Avril (52 percent), Clint McDonald, Tony McDaniel, and Brandon Mebane (50 percent), Bruce Irvin (47 percent), Malcolm Smith (46 percent) and Red Bryant (46 percent). Seattle rotated their defensive line and outside linebackers depending on down, distance, opposing personnel, and opposing team.

What does that mean for incoming or current NFL tweeners? Well, say you lack size at the defensive end position -- you could find yourself playing in pass downs, where opposing teams cannot as easily exploit your deficiency in taking on the run. Say you're extremely stout and strong verses the run but struggle in pass coverage? Play you on early downs or in a role specifically designed to have you on the line of scrimmage, either stopping the run or rushing the passer most of the time. The days of "three-down" players may be coming to a close. A heavy rotation and use of specialized roles for each player on the front-seven certainly helped Seattle stay fresh and healthy for their playoff run.

Recent Tweeners

Regardless, it's still extremely difficult to project a tweener player to the pros. While there is definitely some optimism around them, the jury is obviously still out on several recent tweener types, including Seattle's Bruce Irvin, Cleveland's Barkevious Mingo, San Diego's Melvin Ingram, San Francisco's Corey Lemonier, Houston's Whitney Mercilus, and Green Bay's Nick Perry.

Irvin and Ingram in particular are interesting to me. Irvin was panned as a major reach by the Seahawks as an undersized, underweight 4-3 defensive end, but the 15th overall pick of the 2012 Draft came in and grabbed eight sacks as a rookie. He then made the move to strongside linebacker as a sophomore. The Seahawks saw his athleticism as something they couldn't pass up after he blew up the Combine with these stupid numbers:

There have been hiccups along the way during that transition and he's still got a long way to go, as you'd expect, but Irvin has learned to play from both a three-point and a two point stance, drop in zone, cover backs and tight ends, and he looks somewhat natural doing so despite having played mostly defensive end in a 3-3-5 stack at West Virginia. He will still rush from the defensive end spot at times. He is also used to spy the new-school quarterbacks like Colin Kaepernick in passing situations -- an unheralded but important job for a team whose main adversary is a guy with gazelle speed.

It's unclear if Irvin will stay at OLB or move back to Defensive End in 2014, but either way, that versatility has value.





As for Ingram, the 6'2, 265 pound 3-4 outside linebacker who also had insanely good speed scores at the Combine, the Chargers have integrated him into their defense as a rush linebacker, mostly responsible for getting upfield. He's asked to drop back into coverage at times (and he got an interception vs. the Bengals during this year's playoffs), but for the most part, the Chargers try not to ask him to do what he's not able to do. His career, even after an ACL tear his rookie year, looks to be on the uptick.

Likewise, I imagine for Cleveland's Barkevious Mingo, San Francisco's Corey Lemonier, Houston's Whitney Mercilus, and Green Bay's Nick Perry, their respective teams have high hopes for the upcoming season.

2014 NFL Draft tweeners

In addition to Michael Sam (6'2, 260), players like Auburn's Dee Ford (6'2, 243), Arkansas' Chris Smith (6'1, 266), BYU's Kyle Van Noy (6'3, 244), Arizona's Carl Bradford (6'1, 243), USC's Morgan Breslin (6'1, 250), and Florida's Ronald Powell (6'3, 240) among many others, will be looking to avoid or shed that oftentimes pejorative label. Will they be thought of as too slow to rush the passer, too small to take on the run, too inexperienced to drop back in coverage or too much of a project to put it all together?

As you evaluate defensive end and outside linebacker prospects, watch closely for each player's get off on the snap. Watch for their assortment of moves in their rush - do they have more than one? Do they get engulfed once a tackle gets their hands on them? Do they move easily when dropping. Can they run in coverage with backs and tight ends? Can they take on and anchor front-side blocks in their direction? Can they set the edge or do they get beat outside?

Ultimately, in the modern NFL, for prospects that can do one or two of these things really well, these tweeners, there's an important role they can play in many team defenses.

Photo credits: Matthew Emmons-USA TODAY Sports; Dilip Vishwanat, Kirby Lee-USA TODAY Sports

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