Oregon’s 3-4 Defense: Concepts, Coverages, and Blitzes

I’ve tried to make the 3-4 as simple as possible for it to make sense to a wide audience.  Any questions?  Feel free to post them in the comments and I’ll answer them as I get them.  I’m also happy to go over any plays on offense or defense and talk about what happened on each one.  Request a play by putting the description of the play in the comments section so I can find it and I’ll answer each one with a full post including diagrams.

Oregon's offense has been so good that it takes some spotlight away from a defense that is quietly dominant.

Once Chip Kelly took over as head coach of the Oregon Ducks we saw the defense move from a 4-3 base (although with some 4-2 mixed in) to a 3-4 that runs multiple fronts.  Oregon has since run the 3-4 the majority of the time, but also uses the 2-4, 4-3, and 4-2 sparingly.

While the defense appears to be more complex it is actually simpler for the players to run.  The Ducks are able to play so many guys on defense, especially new players, because of the simplicity of the defense.  The nature of the 3-4 and with some of the tactics Oregon puts in place, it’s incredibly difficult to pass against.  In the past there were a ton of checks and adjustments that would happen before the snap, but many of those have been dropped to reduce mistakes and allow players to think less and therefore play faster.

The 3-4 fits well with Oregon because it puts a lot of speed on the field.  It takes a defensive lineman and replaces him with a faster linebacker.  More importantly, it creates a lot of interesting blitz opportunities to confuse the quarterback.  This means that the quarterback, before the snap, will not know who is coming, who is dropping in to coverage, and sometimes even what the coverage is will still be in question before the ball is snapped.

There are two basic types of the 3-4, the one and two gap system.  The two-gap system is when certain players are responsible for two gaps of the offensive line.  A gap is the space between linemen, the gaps on each side of the center are the A gaps, the B gaps are to the outside of the guards, and the C gaps are to the outside of the tackles.  A player like Terrence Cody are typically given 2-gap responsibilities because they are big enough to take up two gaps and also draw double teams.  Oregon runs a 1-gap system, meaning that each player is responsible for only one gap in the offensive line, and in the case of a run certain linebackers are designated to cover certain gaps.  For example, the defensive tackle could get one A gap, and the middle linebacker the other A gap.  A linebacker may have the B gap on a side and the end may take the C gap.  So players aren’t necessarily flowing to the ball at the first sight of run as much as they are filling gaps.  After the intended hole is seen, players rush to the ball.

On occasion you will see Oregon run a 2-gap, but it is only in instances of passing downs, like 3rd and 8 or 2nd and 11.  The 1-gap system allows Oregon’s smaller and faster players to use their speed to their advantage.  The 2-gap puts a lot of pressure on the player designated to cover two gaps, and thus is used rarely and only in situations where a pass is almost certain.  Teams with huge buffet busters in the middle and on the edges can run a two-gap really well.  You need players like Vince Wilfork, and he’s a Patriot.

When looking over almost every play from the season it’s very hard to analyze what a play call looks like compared to a run or a pass.  This is because linebackers are taught that their first steps are forward to play run first.  Against run or pass on standard downs linebackers will take one or two steps forward to play the run before dropping back once they see it is a passing play.  On obvious passing downs they won’t take steps.  But how the players are assigned to the gap is important to stopping the run.  As soon as the backers see that the play is a run play you’ll see them rush at full speed to their gaps.  Corners are typically staying with their receivers until they hit their deep zone, and the Oregon corners realize it’s a run before they pass off their receiver or before the receiver breaks deep down field.  So seeing how play calls work against the run is very difficult.  Obviously if a drop end drops is supposed to drop in to coverage but he’s getting run at he’s going to be taking his steps forward knowing he needs to drop back and may lose leverage on occasion, but for the most part players were quick to recognize play calls and didn’t provide a large enough sample size of running plays towards players dropping in to coverage to draw any conclusive results.

What Oregon does really well out of the 3-4 is zone blitz.  Zone blitz is kind of a buzzword now among people watch a lot of football, so I’ll go over the most basic formation.  When people think of zone blitzes they most often think of fire blitzes which feature 3 deep players in coverage, most often the a safety and the two defensive backs, with three players underneath, typically linebackers and a safety.

This type of a blitz is an aggressive and safe.  There is a high reward and little risk as there are almost always at least six players in coverage.  The stunts, shows, and delayed blitzes are all to fake offensive line protection so that they basically remove themselves from the play, either by blocking air or doubling on a player.  This is because the looks before the snap confuse the quarterback, cause linemen to block players that showed they were blitzing but dropped in to coverage, but doesn’t give up the deep ball with three safeties deep.  The underneath routes are open but those are most commonly stopped after a gain of about 6 yards, which on downs of 3rd and 8 force punts.

What the 3-4 does is try to very carefully orchestrate the entire defense, so that they move as a unit to free up linebackers.  Linebackers will show blitz, but drop in to coverage, linemen will stunt, and linebackers will delay their blitzes.  This is all in an effort to get one on one matchups and huge lanes for players to move through and get to the quarterback.  I’ll break down parts of the blitzes, from coverage (although limited because of camera angles), blitzes, and stunts.


Stunting is when linemen move as a unit to occupy offensive linemen and create alleys and one on one matchups.  A prime example is a defensive end slanting towards the guard, bringing the tackle with him, and the defensive tackle then looping around unblocked.  The reverse can also be done, with the defensive tackle attacking the guard and the end looping round to fly up the alley in the middle.  The player tries to attack two players, which basically forms a screen for another offensive lineman who thinks he’s going to pass off the defender to a lineman occupied.  I’ll illustrate examples.


Linebackers will work based off the stunting of the defensive line.  If a defensive lineman is slanting one way, you can bet that the linebackers will be blitzing from the side they are slanting from.  The stunts and slants by the line attempt to put offensive linemen on an island with faster players in space or just free shots at the quarterback.  Sometimes there will be a delayed blitz to let the blocking on the offensive line develop, and often times this leads to open alleys to blitz through.  Often linebackers will show and then back off to their coverage’s.  This also causes the line to compensate to one side and create mismatches.  When the quarterback doesn’t know who is blitzing, it creates a problem when calling hot routes.  For example, if the hot route from sight adjusting for a blitz is a slant, the quarterback doesn’t know if the linebacker will be backing off to cover the space a slant would go to, or if the backer is going to come on the blitz.

NOTE:  Most of the zone blitzes will come from the field side.  There are two basic terms in defense, field and boundary.  Most commonly the ball is on a hash mark, so the side that goes towards the middle is called the field, the side towards the sideline is the boundary.  Oregon runs most of the blitzes from the field side.

Importance of Showing Blitz

Showing blitz confuses the line and quarterback because they have to account for them to come.  Oregon will show a lot of linebackers and will try to trick the line.  Often Oregon will rush hard to one side, hoping that the line is playing everyone square up or slide protection to the opposite side, giving an instant numbers advantage.  Also, Oregon will show rushers and drop most of them, causing the line to keep most people in the backfield or on the line in coverage, and giving a huge advantage to the secondary as they have to cover fewer receivers.


As shown above, the most common coverage behind is three players deep playing thirds and three players underneath.  Sometimes you’ll see man-zone combos (which will be illustrated in one example), cover 1-man in some cases, and depending on the down and distance two players deep in a cover 2 and four players underneath.  Most of the time though when someone talks about a zone blitz they are talking about fire and dog blitzes, which feature the three deep in coverage.  Oregon will very rarely put nobody back deep in coverage.  The Ducks will often have one guy back, Boyett, in coverage when there is man coverage on the edge.  Almost all zone coverage’s will be in Cover 3 but sometimes in Cover 2 in certain situations, like 3rd and 3.


Here’s a great example of showing blitz causing adjustments on the line.  Oregon shows the defensive end in a two-point stance and a linebacker and corner on the blitz.  The line is going to slide to the right and the running back is going to take the corner off the edge.  The key here is the defensive end on the backside.  He’s going to attack the shoulder of the tackle and the guard, who doesn’t see the blitzing backer, is going to pick up the tackle.

The MIKE backer fakes the blitz who the guard is eyeing as he’s doubling the tackle.  Everyone on the side towards the field is accounted for by the protection shift and the running back.  However, the tight end on the backside was sealed by the push from the defensive end and is chasing the linebacker through the gaping hole created by the guard doubling the center and the tackle picking up the defensive end.

In order to avoid a sack the quarterback throws an incompletion due to throwing off his back foot.  Based on the positioning of the offensive line they may have been running a screen, but the speed of the linebackers is so overwhelming that with a clear lane a linebacker can get to any quarterback.

Here the defensive tackle is going to push at the offensive tackle.  There isn’t a real threat from the linebacker to blitz to the outside so the line protects to their left and the running back plans to pick up the defensive end who is standing up.  The linebacker in this case is going to loop around the end and the running block to chase down the quarterback.

Here you can see how the offensive line blocked to their left and how the running back is full committed to blocking the end.  The quarterback can see the linebacker coming off the edge and begins to take off running.

Again, Oregon’s speed on the edge is really fast and the linebacker catches up to him.  None of the offensive linemen seem to know the quarterback is already down and we have five linemen guarding three players.  That is a win for the defensive line.  Three plays are being blocked by five, one player had a one on one, and another player had a free shot at the quarterback.

Here’s an example of showing blitz and then delaying.  Oregon has three down linemen and a drop end in (Dion Jordan I believe) who is standing up.  The linebacker is showing blitz but he is going to back off for a moment and find a hole in the protection.  Now looking at the linebacker and the two defensive backs, can you guess what coverage they’re in?

The defensive back on the boundary side (away from the camera) is on an island with his receiver.  The linebacker backed off the blitz but after finding a hole he attacks.  Notice how all the linemen except for one is one on one with an offensive lineman and the running back is between two offensive linemen on the right side, meaning he has a long way to go to block the blitzing backer.

Oregon was running what appears to be man-zone coverage, something they ran a lot of pre-2009.  It’s a little hard on the defensive backs because the coverage is dependent on the second receiver, who is the key player safeties are watching in passing plays.  The second receiver will almost always give away the routes and patterns.  The bunch formation is very hard for defensive backs to pay man on, so the Ducks may have checked in to a man-zone on that side of the field.  Arizona is running a three vertical as the second receiver is running straight but crossing in front of the defensive back, and the inside most receiver is running a short crossing route (a way to beat the fire blitz).  The linebacker quickly picks up the crossing route as the defensive back and safety both pick up the receivers going deep.