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4-3 SAM Linebacker (OLB) – Dont’a Hightower

Some teams do play just left and right outside linebacker, and you may wonder why there should be a difference between the two, but the reason most teams don’t and instead play strong and weak side linebacker is because most offensive formations are not balanced. They have a blocking strength to one side or the other. To counter that you need linebackers with different skill sets on either side of the formation.

These outside linebackers typically have slightly different responsibilities against the run and pass. The SAM linebacker plays on the strong side of the formation, hence the name, and is usually the linebacker that has to take on lead blockers in run plays, or deal with tight ends releasing into pass patterns.

Because of these roles, strong side linebackers need to be stronger and more stout than their counterparts on the weak side. Not every run goes to the strong side of the formation and so there will be some crossover in skills between these outside linebackers, but typically SAM linebackers need to contend with a more physically demanding game.

Complete SAM backers are becoming rare players to find. The abilities necessary to take on lead blockers against the run and still be able to cover athletic tight ends down the field is working the problem from both ends at the same time. The position is therefore becoming ever-more a two-down player — a run specialist that gets replaced when teams go to nickel defense for a more athletic and fluid player in coverage.

Dont’a Hightower is the prototypical 4-3 SAM in today’s NFL – a stout run defender who is capable – if not impressive – in coverage. The Patriots keep him on the field for third downs, but alternate prototypes like James Harrison have been kept strictly a base-formation presence against the run.

Alternate Prototypes: James Harrison

4-3 MIKE Linebacker (ILB) – Luke Kuechly

The MIKE linebacker is the quarterback of the defense. He has the toughest job of the 4-3 linebackers, because he needs to be able to cover the most ground, whether that is sideline to sideline, or dropping into the deep middle. He also has the role, in most defenses, of calling defensive signals and making sure the defense is lined up in the right place and everybody is singing from the same hymn sheet.

When the Panthers moved Kuechly to the middle he was like a different player. His instincts and ability to flow to the football allowed him to rack up an enormous number of tackles and involve him in plays he couldn’t muscle in on when he was left to one side of the defense. With middle linebackers needing to cover large amounts of ground, they are usually more athletic than SAM linebackers, and they must have the best instincts and feel for the game of all because their positioning depends on the speed in which they can read and react to plays.

Kuechly has the ability and range to flow to the football and is adept at reading and reacting to short passes in front of him. He can still struggle a little to adequately feel danger on routes that went behind him, but once he develops the experience to deal with these passes he will be a complete player and a legitimate All-Pro.

Middle linebacker is also the position that can vary the most depending on specific schemes. In a defense that employs a Wide-9 defensive front, the MLB needs to be a much more aggressive and stout downhill thumper, because he must be able to play off the blocks of free offensive linemen coming at him. Conversely, in a Tampa-2 scheme the ability to drop deep down the field to cover passes is the most important skill, which is why Brian Urlacher was such a lynchpin of the Chicago D during the Lovie Smith-era.

Alternate Prototypes: Patrick Willis, Stephen Tulloch

4-3 WILL Linebacker (OLB) – Lavonte David

David is another player who secured his spot a year ago and only cemented it further with his 2013 campaign. The WILL linebacker is the highlight-reel position in the 4-3 defense. Things are schemed for this player to fly to the football and make plays, and nobody exemplified this more than David.

Generally the SAM is tasked with taking on the lead blocks, the MIKE linebacker fights his way through any remaining blocks and the WILL linebacker gets a free run through traffic to the football. The weak side linebacker is therefore usually the quickest, lightest and most explosive of the 4-3 linebackers.

Teams will sacrifice size in favor of speed, quickness and the ability to cover distance and close on the ball and that’s why you often see prospects talked about as being either a strong safety or WILL linebacker. David was a master of the tackle for loss last season, shooting into the backfield and blowing up plays before they had a chance to get going with his speed and explosiveness.

I have said for years that the perfect WILL linebacker template would look an awful lot like Ernie Sims, who has a fearsome level of speed, athleticism and explosiveness in a relatively small frame, but Sims never had the instincts and ability to read the game necessary to take advantage of his physical gifts. Lavonte David is essentially what that fictional version of Ernie Sims would look like – the new defensive prototype for the position – taking over the mantle once made famous in Tampa Bay by Derrick Brooks.

Alternate Prototypes: Sean Weatherspoon, Vontaze Burfict.

3-4 Outside Linebacker – Justin Houston

3-4 OLB is another position that requires new blood. For years DeMarcus Ware was the prototype for the position but injuries, age and a change in scheme in Dallas before he moved on have all meant that we can begin to look elsewhere. In many ways 3-4 outside linebackers have far more in common with 4-3 defensive ends than they do with any of the 4-3 linebacker spots. Many of the league’s current 3-4 OLBs have at some point in their careers been asked to play 4-3 DEs as new coaching staffs and schemes have come and gone.

They are the primary pass-rushers in that defensive scheme. They are essentially just stand-up defensive ends, the 3-4 began as a way to rush the same number of players (four) as a 4-3 front but without telling the offense which four were coming before the snap. This change meant that while a defensive end may be asked to drop into coverage a handful of times in a season as part of a zone blitz, a 3-4 OLB has to be expected to do it on a semi-regular basis.

Teams still value their pass rush far more than their coverage, and a talented rusher will always have a place in a 3-4 even if his coverage is questionable at best, but our new prototype for the position dropped in coverage just 106 of 724 snaps last season.

With Ware out of the picture at least for the moment the new prototype is Kansas City Chiefs OLB, Justin Houston. At 6-foot-3, 258-pounds, he has the length teams want (height and arm reach) in order to fight off offensive tackles and keep them at a distance, but he also has the speed to turn the corner and influence the quarterback on passing plays.

3-4 OLB is a position in which the textbook player has begun to be chipped away at. Though Houston fits the bill in terms of the body type teams typically looked at, more and more we are seeing teams find a way to utilize talented pass-rushers whether they are 6-4, 260 or not.

Alternate Prototypes: Clay Matthews, Aldon Smith

3-4 Inside Linebacker – Patrick Willis

The 3-4 inside linebacker is similar in many ways to the 4-3 MIKE ‘backer, and Patrick Willis could easily be named the prototype for both positions, having succeeded at both already in his NFL career as the 49ers changed defensive schemes. Willis is the league’s best inside linebacker regardless of defensive front, and the differences between the positions are subtle. Inside linebackers in a 3-4 usually don’t have to cover as much ground as their 4-3 counterparts, since there are two players splitting the field in half, coming forward against the run or dropping back into coverage.

The flip side to that arrangement is they usually need to be more capable of dealing with blocks from offensive linemen getting through to the second level because there are only three down linemen in front of them instead of four. That is made even more pressing by the move away from two-gap defensive systems towards more one-gap attacking fronts.

In an old-school 3-4 scheme the linebackers could rely on giant man-mountain defensive linemen in front of them eating up two blocks each, but today those linemen are smaller, quicker and attack gaps rather than occupy blocks. 3-4 inside linebackers consequently have to be able to attack gaps behind those linemen, plugging holes and stuffing the run at the line of scrimmage.

Just as some teams that run a 4-3 play just left and right outside linebacker, some 3-4 teams will play strong and weak side when it comes to their inside linebackers, whereas some play just left and right side. For the teams that don’t specify, either of the inside backers can be expected to take on the role of the SAM, attacking lead blocks and creating the play for the trail player to make the tackle depending on the point of attack.

Willis is a wrecking ball for the 49ers. He has off-the-charts athleticism and the burst to attack plays both against the run and pass. He also has more than enough strength to take on blocks when he needs to, whether that be in the run game or even coming on a blitz through the middle. Willis is the league’s best inside linebacker by a distance, and remains the league’s prototype.

https://www.profootballfocus.com/2014-defensive-prototypes-linebackers/

....depends on defensive alignment for offensive positioning