Applying Saban’s Match 3 Principles to Split-Field Quarters Defenses.
Everyone can agree, Nick Saban knows defense. In fact, according to BCfToys.com, which rates college defenses on their efficiency and is “adjusted for the strength of opponent offenses faced,” has never placed Alabama outside of their top 10 in the past five years (low being #7 in 2014 – the only time they were out of the top five). In the past three years, Alabama has been either #1 or #2 in defensive efficiency. One of Saban’s bread-n-butter schemes is his Rip/Liz or Match Cover 3. This single-high coverage is crucial to his run defense and is adjusted to defend the offensive counter move in the four verticals.
Many defensive coaches are familiar with Saban’s Cover 7 schemes that he uses to defend spread teams from a two-shell, but his Rip/Liz tends to be the “go-to” coverage during base downs. Even Clemson has become a heavy user of the Rip/Liz concept, using the scheme to dominate ACC opponents (and also being in the BCfToys’ top 10 in defensive efficiency the last 4 years). Needless to say, the Rip/Liz concept is an important scheme that every coach should familiarize themselves with, even Quarters coaches. What makes the coverage scheme unique is its structure and how Saban decides to spin the secondary (and protect the seams). It’s something defensive coordinators who base out of Quarters coverage understand – Never roll strong.
One of the unique ways Saban protects his defense is in the way he inserts the extra box player. Cover 3 and any single-high coverage is designed to maximize the box players. By spinning, the defense has created overhangs and cover downs to the slot players. These overhangs enable the box players to eliminate their conflicts. In a typical Quarters defense, at least one linebacker will be in “conflict.” This conflict player is typically where spread offenses attempt to attack the defense with RPOs. In the illustration of a typical Quarters defense below, the Will LB is the conflict player. He must fill the open “B” gap while covering down to the slot. Saban and teams that base out of Rip/Liz reduce the conflict for the Will by spinning the safety to his side over top the slot (DS).
In Rip/Liz, the weakside safety is usually the spinning safety. By spinning weak, Saban is ensuring that his front side pass distribution is intact. Versus a basic 2×2 set this allows the ILB closest to the RB to vacate the box if the RB flares because the backside safety can fold into the box vs a QB run and in the pass the Will can handle the middle hole. Where the weak spin helps is against single WR sets (3×1/2×1). Many teams will choose to spin to the Trips side or the passing strength, but this can be dangerous because the defense loses an overhang to the boundary (and exposes the backside CB to a one-on-one matchup). Continue reading “Learning How to Spin – Adapting Saban’s Rip/Liz”
Welcome to the Big 12 where Dime has now become your base.
The Big 12 has always been on the outer limits of what coaches are willing to do on offense and a graveyard for “guru” defensive coordinators (just ask Diaz and Strong). Defenses in the Big 12 play more snaps than the average Power 5 defense. Tempo and the Air Raid reign supreme in a league that prides itself on scoring points. The knock on the league has always been the defenses in the conference. To many outsiders, the Big 12 is offense first, and it is, but if you are looking to defend the spread, there is no other place to look – they live with it every day.
If looking at defensive stats alone, the Big 12 is on the outside looking in, but there is something to be learned here. Starting in 2016, teams in the Big 12, primarily Oklahoma St. (2016) and Iowa St. (2017), began using a modified Dime (3-down) and Nickle (4-down) package to combat the Air Raid heavy teams in the league. I discussed in January’s article about how teams are becoming more fluid in their fronts; switching from 4-down to 3-down without losing scheme.
The Dime package utilized by Iowa St. in 2017 was no different. Versus a run-heavy Oklahoma team, the Cyclones relied on a modified 4-down defense to defeat the Sooners in Norman. There ability to switch from a 4-down to a 3-down without subbing made the scheme a perfect fit for the multiple Sooners. With a TE like Mark Andrews and an H-back like Dimitri Flowers, the Sooners could give multiple looks without subbing. This fact alone is why the Big 12 is so innovative on defense. Hybrid players are a premium in the league. In Iowa St.’s season finale versus a high-powered spread attack in Memphis, Iowa St. utilized the 3-down version of their hybrid Dime to defeat Memphis 21-20.
The Dime/Nickel hybrid defense has become Iowa St.’s base defense and is fluid between the different front structures. When the Cyclones go 4-down, it is no different than if they are blitzing a linebacker from their Dime package. The coverages are similar too. Here is a look at the two base defenses:
Oklahoma St. Nickel (4-Down)
Cyclone Dime (3-Down)
Continue reading “Running Dime as Your Base – A Lesson From the Big 12”
Dog Check: A five man pressure package built with BTF principles.
I get a lot of questions about packaging blitzes and how to go about doing so. I’ve written several pieces on the subject:
In the first article, I detail the theory behind the concept and briefly go over the setup process. In “Building a Better Blitz,” I detail how to design and use formations to create an adaptive Zone Blitz. Packaging blitzes are nothing new. Many coaches understand the concept of “blitz the formation,” or BTF. Coaches like Belichick, Rex Ryan, and Saban use the offensive formation to determine how to attack.
This concept of “packaging” blitzes/pressures from the same tree allows the defense to adapt to any situation the offense may throw at it. Generally, the most common way defensive coordinators utilize BTF is in their “all out” or max blitzes. The easiest way to demonstrate the whole process is to actually create a blitz package.
Below is Dog Check, a single-dog (one linebacker) pressure. It is a five-man pressure that uses an edge blitz by the LBs and a simple line movement. Each pressure within the formation is named and is unique, but when combined together, the “check” can now adapt to any formation reduce the guessing. The adaptiveness and flexibility that checks give to a DC are invaluable. Being able to eliminate verbiage and guesswork can be the difference between a tackle for loss or a touchdown (especially when tempo is involved). Continue reading “MQ’s Single-Dog Blitz Package”
Defending single-width formations.
There are certain formations that pop up during a season that can give a defensive coordinator pause. Unbalanced sets, for instance, are used by many offenses to force 16 to 18-year-old athletes to think on their feet or force a defensive coordinator to burn a timeout. Pro spread offenses use tackle-over sets to confuse the defense and gain leverage, while 10 personnel spread and two-back offenses utilize unbalanced sets to work quick motion from the single receiver side (“X-off”). Though “nub” formations are not unbalanced, they are very similar and continuously give defenses trouble. When the formation is combined with RPO and Air Raid schemes, it can put immense pressure on DCs.
Single-width formations are paradoxical. On one side an offense has multiple receivers, while on the other it has a running formation. “Nub” formations force the defense to acknowledge a true “run” side, while also defending multiple receiver formations. Offenses that utilize TE sets can create leverage issues or force a secondary player to be left by his lonesome against a bigger player. Many defenses will choose to spin against “nub” formations to gain extra men in the box and replace lost overhangs.
As modern football progresses, more offenses are choosing to go away from under center formations. This allows the offense to have a two-way go in a Pistol formation or a “read” side in an RPO offense from the gun. There is nothing more threatening than an offense that is powering the ball down the field while implementing RPOs. Packaging plays forces the defense to stay even and protect the run fits and pass distribution, all at the same time. Instead of spinning, a defense needs to stay in a two-shell look and develop a game plan dependent on the tendencies and personnel preference of the offense. Continue reading “The “Nub” Side”
How to adjust to TE sets without a natural adjuster.
Spread and Pro-Style offenses utilize a Tight End versus three-down defenses because the defense lacks a natural adjuster. Unlike a four-down defense that can distribute their anchor points evenly across the formation, the 3-4 lacks the extra lineman to defend the extra gap (hence the name “Odd Front”). When faced with an 11 personnel formation, many 3-4 defensive coordinators choose to spin to single-high coverage to gain an extra man in the box. Another adjustment for many DCs in this situation is to attach the outside linebacker to the TE’s side. With the loss of a coverage man and overhang, the DC is forced to spin. When defending an 11 pers. offense from a 4-2-5 or 4-3, these little adjustments aren’t needed because the anchor points are evenly distributed and don’t need to be created.
In a four-down scheme, the defensive ends act as the walls of the box. When a TE is introduced into the formation, the DE to the TE’s side moves to a 9 technique (unless it is Trey and then he is in a 7 or 6i). The four defensive linemen allow the defense to stay even and adjust with the linebackers and secondary. The evenness of the four-down is why many spread teams attack 4-2-5 and 4-3 defenses from 20 pers., utilizing an H-back. In 20 pers., the offense can use the “H” to attack either side of the defense, reading the overhangs to determine what play to run. If the “H” was attached to the formation (TE) he would lose his two-way go.
Defending 11 pers. formations from a 3-4 boil down to understanding how certain fronts react to the extra gap. From a single-gap fit 3-4, a defense can easily adjust to TE sets and stay within a two-shell scheme. The lack of an adjuster is an issue, which is why many 3-4 teams that face the spread, and Pro-Style spread, choose to defend from an Okie Front because it reacts much like the four-down Under Front. Using the offense’s formations as a guide, it is easy to build simple rules within the defense, setting the strength and when to attach the OLBs, to alleviate the issues seen in many 3-4 defenses. Combining an Okie Front with a match quarters scheme can adapt and flex with any formation an offense throws out, it just boils down to how a DC chooses to line up.
Continue reading “Defending 11 Personnel from a 3-4”
Defensive schemes to combat spread offenses.
Introducing MQ’s first full-length book, Cautious Aggression: Defending Modern Football.
Buy it on immediately on CreateSpace, Amazon, and Kindle. Click the provider below and order your copy today (Links open in new window).
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Description: As the spread becomes more of the norm in all regions of this country it is important for coaches everywhere to have a resource for defending the modern spread offense. Cautious Aggression: Defending Modern Football is that resource for coaches. The schemes described in this book are tried and true methods for defending some of the best offenses this country has ever seen.
Starting with “The Why” and ending with “The How.” Cautious Aggression gives coaches a defensive philosophy they can trust. Using diagrams and concise explanations, the book lays out a formula for success for coaches to utilize in their own schemes. Below are the chapters:
- Argument for Two-High
- Defending the Modern Spread Offense
- Defending Run/Pass Options
- Systematic Creativity of a Quarters Defense
- The Art of Match Quarters
- All About the Cover Down
- Designing a Modern Defense
- Setting the Strength
- Defending Formations into the Boundary
- Defending Motions
Coaching at the lower levels of football bring its own issues to the table that many Division I football teams do not face. Cautious Aggression: Defending Modern Football is written for all coaches. The experiences Coach Alexander gained while coaching for Baylor Football combined with his experiences at the high school level has given him a unique perspective on defensive football. Many of the concepts and theories in this book have been adjusted to fit the needs of high school and small college coaches around the country. Come learn “The Art of X.”
Thank you to all that support the site, this book would not be possible without you.
Kick the coverage with out the spin.
The biggest issue facing defenses when defending 3×1 formations is the run/pass conflict of the Mike. No other player in a 3×1 formation has more on their plate than the leader of most defenses. In modern football, the age of a “plugger” at Mike is over. Each LB must be able to cover underneath routes and understand how their run fits relate to their pass drops. Defenses can no longer afford to drop their LBs to “zones” or landmarks. Each player is a link in a chain. As the spread becomes a permanent fixture in most regions’ football cultures, defenses are turning to match schemes to help alleviate the issues seen in traditional defenses.
Traditionally, teams have spun to the three-receiver side to allow the Mike to stay in the box, switching his responsibility of relating to the #3 receiver to “plugging” the middle of the formation. Eliminating this run/pass conflict helped defenses against the “spread-to-run” offenses but it opened them up to high percentage throws that could easily become fatals (TDs) when those offenses ran play -action. In the diagram below, an Over Cover 3 scheme is shown:
Right away, the main issue with Cover 3 or “kick” coverage to Trips is the backside corner is in man-to-man coverage with the single WR. Offenses traditionally have left their best receiver at the “X” because of this defensive scheme. The best offensive receiver on the field is lined up across from a player with little to no help. This can spell disaster for defenses. As the spread as evolved, offenses have developed reads for the third level. If a defense spins to a 3×1 formation (“kick”) the offense can easily check to a backside choice route depending on the leverage of the corner. For most, this is a post route ran right off the back of the kicking safety. This is a high percentage throw that can spell disaster for defenses. Continue reading “Defending 3×1 Formations – Solo Coverage”
An introduction to the three down Dime package.
One of the greatest luxuries in football is when a defense has enough depth in the secondary to create a Dime package. As spread has become the norm in football, the Nickel package, replacing a linebacker with a secondary player (usually a safety), has become the norm and many defenses’ base. Most teams have “tween” or hybrid players. Utilizing these players on defense has made it easier for defensive coordinators to adjust to the onslaught of spread teams. The Dime package, in particular, is different than its sister the Nickel package. Instead of replacing a LB with a safety, the Dime package puts two defensive backs in and replaces either two LBs (four-down) or a LB and a defensive lineman (three-down). The specific package being discussed in this article will cover the three-down, three safety Dime package most generally seen in college today.
A 3-4 Base
If a defense’s base is a 3-4, it can easily adjust to the spread by putting a Nickleback at Sam, much like its counterpart, the 4-2-5. A three-down Dime package takes the Mike off the field and inserts either a safety or a CB depending on the DC’s preference and the scheme being used. The front most used in a Dime package is the Buck Front or a 505 front. This ensures an edge rusher on either side of the quarterback that will define the box. The Nose’s role is to get a vertical push on the pocket and make the QB move. Below is a diagram of a 3-4 Buck Dime Package:
The first decision that has to be made when developing a Dime package is who is going to be part of the Dime package personnel? If looking to run more of a man scheme, a DC is more likely to bring on two cornerbacks and leave the two most athletic LBs on the field. As stated earlier, more defenses are shifting to a Nickel/Hybrid base. This means the traditional Sam LB is actually a safety. In the case above, the Nickelback is more than likely a third CB while the Dimeback is another safety. Continue reading “The Dime Package”
If the offense won’t throw to #1, lock him up and reduce the field.
When defending a team that runs Trips it is important for the defense to have multiple coverage options. Depending on how an offense chooses to attack a defense the selection of the right coverage can be crucial. Being able to switch from base coverage to base coverage allows the defense to keep the offense on its toes. If a defense only runs one base coverage against Trips, offenses will quickly find a way to exploit it. This fact alone should encourage a defensive staff to carry multiple coverages into a game and be able to use them when the opportunity arises.
Many times offenses use the #1 receiver as a decoy or chooses to run him off to create a void so the #2 or #3 WR can run an out route into space. One way to counteract the nonuse of #1 and outs by #2 or #3 is to run Special Coverage. Unlike Stress where the Sam is blind to what the #3 WR is doing, Special eliminates the #1 completely and reduces the field. The Sam takes on the responsibility of a Two-Read CB. His eyes are squarely on #2 and will carry the vertical of #2 if the offense runs vertical routes. Like Stress, the key player is the Sam linebacker and his ability to run with a vertical route. Eliminating #1 puts the Sam on an island with #2. As stated earlier, having options in coverage is important to defending the spread. A defense must be able to adapt to any situations and adjust to any formation/scheme thrown at it. Continue reading “Defending Trips – Special Coverage”
A “how to” guide to defending the Air Raid’s top pass concepts.
With the birth of the Air Raid offense under Hal Mumme and its expansion under Leach, the Air Raid concept has flourished alongside the advancement of the spread in modern football. The Air Raid offense, in particular, is married well with the no-huddle concept and can be run out of multiple formations even with the added effect of tempo. True Air Raid offenses base out of 20, 10, and 11 personnel sets. Many of the concepts needed to run the offense utilize 2×2 and 2×1 sets to put pressure on the defense’s back seven.
The Air Raid offense and its vast offshoots still boil down to several basic concepts. The key to any Air Raid offense is the use of “triangle” and simple high-low reads. The offense has been used to rewrite many record books and its concepts are present in most modern spread offenses. The main way Air Raid teams attack a defense is the soft middle of the field left by vertical pushing routes with the outside wide receivers. This vertical push forces the safeties in a two-high look to climb with the outside WRs. The zone dropping linebackers are left to defend WRs coming from the opposite way behind their view. These simple crossing routes are deadly to a defense that cannot get support from the backside safety or simply spot drop. One way a defense can counteract the Air Raids propensity to attack the soft middle vacated by the boundary safety is to run “Steal” coverage.
Unlike “Read” Coverage that takes advantage of the offense attacking the front side triangle (think pick/flat/corner), “Steal” coverage uses the boundary safety as a “robber” for the crossing routes. Much like its sister versus Trips coverage “Solo,” Steal uses the boundary safety as a spy on a front side WR. The main objective of the DS in Steal is to read the crossing route and hold his ground in the window vacated by the Will LB. The diagram below demonstrates Steal Coverage: Continue reading “Steal Coverage to Combat Air Raid Offenses”
Running an Okie Front to defend the modern spread attack.
Defensive linemen are at a premium. For many teams, it is hard to field a deep roster that can lend itself to a four-man front. Running parallel to the defensive dilemma of lineman depth is the popularity of the spread. A natural conclusion for many defensive coordinators around the country has been a shift away from a four-down front and into a 3-4 scheme. The flexibility of the 3-4 and the added athlete on the field makes the scheme spread friendly. The multiplicity within the scheme allows DCs to attack the offense from multiple directions without sacrificing pass distributions. Running a two-high scheme behind a three-man front meshes well with teams that have a history of running a 4-2-5 or 4-3.
The Okie Front, in particular, can be of service when defensive coaches are looking to defend the spread from a three down front. With a 5 technique, a shaded Nose, and a 3 tech. (or 4i) to the weak side, the Okie’s anchor points fit the spread much like its four down sister, the Under Front. To the weak side, the Jack linebacker (boundary OLB) is technically a wide “9” in the run fits and controls the edge of the box to the boundary. The Jack LB, in particular, is useful when defending offenses that like to attack the boundary through the air. Even though the Jack is technically a conflicted player (he is responsible for the “C” gap), his alignment allows him to read the offensive tackle and slow play the run. In most four down fronts, the boundary OLB (Will) is the “fold” player and is considered conflicted because his gap is in the box. The Okie Front eliminates the fold and replaces it with a loose overhang (much like a natural Will/DE exchange in a four down front). Continue reading “Defending the Spread From a 3-4”
The Convention, this week’s FAQ, & tips for installing Quarters.
AFCA Convention ::
The AFCA Convention is always a great time. For me, it is a time that I get to see old friends, meet some new, and just hang out with like-minded people. Football has always been an important part of my life. The Convention is awesome because it allows me to give back to my dad who has been a selfless coach his whole adult life. There’s nothing more special than showing my dad around, talking football with him all day and letting him meet people he otherwise would never meet (for instance RC Slocum). Many go to look for new opportunities to move up, but keep in mind, if you consistently chase the cheese could become blind to a great opportunity. This profession is built on relationships. As you walk the halls of the Convention you will see every type of coach, but don’t be the guy looking through the person you are talking to so you can get to a “more important” person. When I was ending my GA experience at Baylor, Coach Bennett reminded me, “The people we meet going up are the same as we meet going down.” Treat everyone with respect, because you never know when they may help you out. For most of us, we all start as GAs or interns (It took me a whole calendar year, and some luck, to get paid at Baylor!).
The Convention makes everyone equal as well. There is no other place in this sport where the head coach at a Power 5 school will rub shoulders with a brand new high school coach, but that is the beauty of the Convention. It is a truly special place where football coaches can come and be around like minded men. If you have never been it is truly an awesome experience. I would encourage any young coach to go and just walk around, sit in some sessions, and learn something new. It is important that coaches stick together. The age-old saying “iron sharpens iron” is true, and for this profession to continue to flourish in a society that devalues the sport we must raise each other up. [FYI – Next year’s session is in Charlotte, NC] Continue reading “Post-AFCA Grab Bag”
A clinic on the pedagogy of match quarters. Pt. 1 — Teaching the CBs.
Teaching the Corners
Four Read (Sky)
The corner’s alignment in Sky should be front toe at six yards and shaded to the “inside eye” of the receiver. The term “inside eye” means if the CB were to walk up to the WR his outside eye should look directly into the inside eye of the WR. This allows the CB to hold inside alignment without giving up too much space in between. Six yards is a good depth because it is not too deep that it automatically gives up the underneath and not too close that the CB ends up in “no man’s land.” The CB’s stance is an “open” stance or the inside toe on the heel of the outside foot. I’m not a big proponent of getting the butt to the sideline and shuffling out (basketball style) because match quarters is different than true zone. It is essentially a hybrid man scheme, where the CB takes the #1 WR a majority of the time (and the safeties bracket the #2 WR with the outside linebackers). I like to keep my corners square in order to break on the out and slant routes. I find that as players shuffle out basketball style and butt to the sideline, they start working to the sideline and give up the advantage of inside alignment. The point of match quarters is to force the least percentage throw, the fade or deep comeback, thus, I keep them square and we “slide” out.
The initial step of the CB is to slide out, or step-replace for three steps. Most offenses will attack quarters in the soft underneath zone. The slide technique is essentially a three-step read. We are pushing off with the front foot and stepping back with our inside foot. These are quick steps and our feet are never too far off the ground. The corner should have “hot” feet and stay in his “tuck.” This positioning allows the CB to drive on any ball underneath, essentially off-man. After the initial three-step read, the CB transitions into his regular backpedal, reading the WR’s departure speed.
The CB’s eyes are looking at the #2 WR through the QB. This completes his “triangle.” It is important for the corners to be able to see through their entire peripheral vision. Keeping an eye on the departure speed of #1, while reacting to the route of #2. In Sky coverage, the CB is the deep player. His responsibility is to “top” the deepest route or drive on anything underneath by the #1 WR. The only route combination that changes the assignment of the CB is a stop/corner, or China/Smash route. In that case, the CB would give a “stop” call, flip his hips to the sideline and mid-point the stop and corner route (same as in Cloud or Two Read). If the team is running a stop/bender concept to hold the OLB in the curl, the CB should drive on any ball thrown to the #1 WR. Everything is predicated on the #2 WR. In the video below you will see a good example of sliding out and keeping inside leverage by the field corner.
Continue reading “How I Teach Match Quarters – Pt. 1”
Match Quarters pass distributions explained.
When implementing a quarters scheme, Four Read is the Day #1 install coverage and a DC’s most likely first down call. The Cover 4 scheme allows the safeties to be ultra aggressive to the run, yet hold a two-high shell and keep the defense balanced versus multiple formations. Defensive coaches lean on the Cover 4 scheme because it allows the defense to essentially create a nine-man box versus spread sets. For most spread teams, the OC does not account for the two safeties (they are not physically in the box, or fold players). This is where teams running a quarters scheme gain an advantage. DC’s used to rely on a true Cover 2 scheme to gain the hard edge of the CBs against the run. This left the defense vulnerable on the edge of the box, passing lanes in the middle of the field (high completion throw), and put the Mike in a run/pass conflict. As modern football has turned to the spread (and RPO style), more DC’s are turning to the variations of match quarters to answer their run and pass distribution problems. In a previous article (The Art of Match Quarters), I touched on the basics of pass distributions of Four and Two Read. In today’s article, I will go in-depth on the intricacies of each versus popular route combinations.
Continue reading “MQ’s Four and Two Read Pass Distributions”
Theories on attacking the Spread’s cluster sets.
One of the hardest sets in football to defend is the cluster or stack set. Spread offenses utilize this set to get the defense’s outside linebackers in run/pass conflicts. Unlike a traditional 2×2 set, the defense has to adjust to the width of the receivers. Stacking them creates width, and width creates the conflict.
Spread teams rely on the open “B” gap to build their RPO’s into their offensive gameplan. By stacking the receivers out wide, the defense is forced to adjust. In a two-high system, the player in conflict (usually the Will LB) has to choose, cover down to his receiver or hold tight to the box. If he stays close to the box, the offense is going to throw the quick screen and create a 1-on-1 open field tackling matchup with the safety or corner. In most cases, the defense wants to avoid this as much as possible.
On the other end of the spectrum, if the defender widens to the cluster set, the offense has a 4-1 box and a clear running opportunity. Versus a two-high system, there is a great chance for the offense to part the field like the Red Sea for a big gain. Ask any offensive coach, a 4-1 box is a magical thing.
In the image below, Penn St. is running an Under Front and “hips” it’s Sam LB to the strength (“hip” refers to the OLB aligned on the outside hip of the DE). In most RPO style offenses, this is a clear pass read. The Sam has to honor the run read and step to his gap. Even with zone away and a gap exchange with a “heavy” DE (in this set the DE has dive), the Sam has to take a step towards the box. The QB is taught to read the Sam’s path and throw the screen.
Penn. St. is most likely in a “Cloud” coverage (Two Read) and the safety is bailing on the snap. Easy pickings for any decent offensive coordinator. It’s a conflict of philosophy; the offense wants 1-on-1 matchups and the defense wants a plus-one. In order to create a six-man box and protect against the run, the defense has to spin to single-high, but to keep a plus-one in pass distribution it has to stay in two-high, something has to give. MatchQuarters explores the options.
Continue reading “Defending Stack and Bunch Sets”