Island of the Dead, Arnold Böcklin, 1880

Pressing tactics have become progressively more intricate in the last decade. Notions of high and low press have now been complicated with pressing traps, triggers, and most notably–cover shadows.

The latter, a lucid term that connotes the effect of placing a defender along the line of a potential pass route, has blossomed into common soccer-speak. The principle is this: instead of pressing the player on the ball, or the candidate for receiving it, you almost counterintuitively mark the space between them. Previously, this positioning has tended to be linked with a lack of decisiveness, a wavering between two options, and an indication that a defender lacks conviction, but its new deployment as a deliberate tactic has allowed for a resurgence in much kinder lighting.

The options can be seen in the short video below.

Marking the target creates a narrow shadow, in which a simple dismarking movement on behalf of that same target can create passing lanes outside of the defender’s reach. Marking the carrier might seem to cast a massive shadow–which it does, momentarily–but this can very easily be sidestepped with a dribble by the carrier. This movement exposes a passing lane, and now, leaves the defender marking a totally different seam, and largely out of position to recover.

Marking the space, more interestingly, falters when opponents seek to deploy either of these solution methods. Neither dismarking by the target, nor the carrier, is sufficient to clear out of the cover shadow’s way. This is an attacking conundrum. Further fortifying the space-marking approach, this intermediate defensive location means that a presser won’t get caught out of position by tracking too high up the field, nor concede too much space by being concerned with the ball’s destination.

By carefully placing oneself in the middle, the leaders of a press can more strategically organize themselves, independent of the specific positioning of the opponents. I’ll note, this is particularly beneficial when attacking teams will often look to interchange players to confuse pressers and create a free man. Instead of chasing targets, for instance, the goal is to simply take them out of play by intercepting the passing channel. It’s more efficient, and thereby, less tiresome. Look at how effectively the 4-1-3-2 red team can prevent the 3-5-2 blue team from building up, by using midpoint, space-marking, defensive placement. Their position is carefully restrained and not overly-stretched, yet their impact is significant.

And so, with the proliferation of this defensive concept, today we dive into just how we might beat it. I’ll propose three, maybe ~four~ methods:

  1. A direct route from carrier to target
  2. An indirect route from carrier to target
  3. A decoy using the target
  4. Something a little special

Method 1: The Shoulder Cue

Method 1 for getting around a cover shadow involves finding a way to directly get the ball to the very player being obfuscated by the cover shadower. The notion is inspired by another rising passing-skill: the usage of body shape to disguise a pass. It works as follows:

We start with two players, one on the ball, and one off it, and an opposing defender smack in the middle. Since the cover shadow player is nearly always facing the ball–namely why we call the cover they cast a “shadow”, as the ball plays the optical role of the sun–we can use their blind spot to maneuver them out of the way. If we can’t escape the shadow with target dismarking or carrier dismarking alone, then what if we can convince the marker to simply step out of the way?

Typically in the run of play, a defender adjusts their position based on a mix of checking their shoulder, verbal cues from teammates in behind, and most critically, observation of the ball carrier’s body shape. This interpretation of the carrier’s unspoken physical language is an effort to predict the future, instead of react to an instantaneous event (i.e. lunging for the pass itself), and can either be conscious or sub-conscious. While defenders are often more skilled at ignoring subterfuge, attackers that lead the pressing effort are invariably less-disciplined. Thus, we can take advantage, and cast the bait. Sergio Busquets has made a name for himself, largely due to his trademark disguised passing.

In our tricky passing scenario outlined above, the carrier, let’s say a right-sided centerback looking to find the right fullback, will adjust their shoulders so as to suggest that they’re about to pass either to the left or the right of the cover shadower. In a building-up-out-of-our-own-half setup, these two options would translate to a more advanced ball or a shallower one; one is more progressive, the other, more conservative. The key here is that their foot-planted position doesn’t really change, it’s simply the orientation of their torso that rotates. Observe how Busquets doesn’t exactly move anywhere at all; he just suggests that the ball path is one way, and delivers it through another.

In the grand scheme of things, the move might look something like this:

In using the shoulder cue, we’re able to magically move the cover shadower aside. It’s critical to note that the cue can occur in two different sequences: one starting with the carrier, as shown, but another that begins with the target, as seen below. Either one enables our manipulation of the space-marking defender and leaves them in no-man’s-land.

The latter demonstrates a potential improvement upon our former method: if the carrier’s shoulders, hips, and eyes move, while the target’s body actually does so, in the opposite direction, the sequence can be made even more effective. If our carrier starts the move, the target might respond by shifting in the opposite direction from the disguise, freeing up a larger channel to pass into.

Therefore, the skill here, isn’t so much in who initiates the uncovering method, but the coordination between both in-possession players. If the carrier starts, swivels his shoulders, and the target also falls for the deception, then the middle-man will be correctly moving into that seam. Instead, there must be another more subtle cue developed in which both blue players understand the trickery ahead. At worst, it simply needs to become an understanding between the two.

The final complication that might improve upon our shoulder cue is if the space suggested by the carrier as the new passing lane actually ends in a player that might receive the ball. If we imagine a more conscious space-marking defender who has some spatial awareness, they might not be duped by a shoulder cue towards nothing. These opportunities appear all across the field, and we’re better off making our passing deception as “real” as possible.

Method 2: The Power of Triangles

The second method for beating the cover shadow involves actually passing to that decoy, first. Our previous ideas towards how a build-up team might beat a carrier-marking approach or target-marking approach involved sharp lateral dribbles, individual ways to render the cover shadow useless. These solutions are the ones available. A cover shadow, by nature, is a linear device; it’s a tool that is useful for when there is one carrier and one target, but it falls apart when we introduce the ability to change angles with passes, not just sideways dribbles.

Thus, this method requires more components, but will equally challenge someone looking to mark the space between carrier and target. If our passing path starts as a line and evolves into a triangle, marking the space in the center is like giving up in rondo–now, you’re truly not achieving anything.

And while our ability to cleverly undo a 2v1 defensive effort may be strong after employing Method 1, Method 2 reduces the need for disguised passing and dismarking movements, and instead relies on a cohesive effort to create field shapes that can’t be so easily covered by a single player. It is likely that such an idea would be prudent to implement all over the field.

Now we might consider a separate notion–the introduction of two defenders, instead of just the one. Here exists a method for marking the space between the carrier and each of two targets, and seemingly, an excellent solution.

But if we consider this problem in terms of degrees of freedom, and the error-free organization required to execute an effective space-marking press, Method 2 still shines. Let me explain.

If you’re less interested in an engineering-oriented detour, feel free to skip this section! I’ll make an underlined note of where you should pick back up, down below. If you like this kind of thing, like I do, read on.

Degrees of freedom is a term commonly used in engineering mechanics to define the potential domains of motion any specific part has, amidst constraints. It’s also ubiquitously applied in statistics, though I’m less familiar with that side.

Imagine a series of connected “linkages”, as they’re known (just envision solid bars in a mechanism). Some might pivot in 2D about joints with respect to one another, while others slide in one-directional slots. Some are entirely fixed while others are entirely free to roam. These parameters, along with the quantity in which they appear will indicate to us how many degrees of freedom exist. You might imagine that a series of bars all bolted into one confined position would have a pretty low “DOF”. Two base bars that have joints and slots with lots of linkages are likely to have a higher amount of “freedom”, by comparison.

The usage of this concept illustrates how systems behave under various inputs. The visuals that can be made, as a product, are actually quite soothing. If we constrain a design in various ways, it’ll move differently than if we alter those constraints. Here are two examples of identical systems that behave drastically differently based on how we restrict the motion of the center-piece. On the left, a blue triangle has three joints at each of its vertices, while its center translates along a square path. On the right, we can see the same series of linkages, but with the blue triangle pinned through its center (restraining lateral motion), and oscillating after some perturbation.

For those mathematically-inclined, the relatively simple math that governs degrees of freedom, for what’s called a “planar kinetic chain”, is known as the Gruebler Equation. Here, DOF represents degrees of freedom, N serves as the number of linkages, J1 is the quantity of 1 DOF joints (i.e. a pin that removes xy translation and leaves only rotation, or a slot that removes rotation and restrains to a linear motion), and J2 is the quantity of “higher-pair” joints (two sliding-contact cam surfaces, or a gear).

DOF” = 3(N-1) – 2J1 – J2

In essence, the more parts we have, the greater potential we have for freedom of motion. The larger N is, the larger DOF can be. Restraints in the forms of J1s or J2s hold us back, restraining motion. The ones that restrain us more (i.e. those that eliminate 2 ranges of motion, down to only 1 DOF) have a greater impact on our overall DOF. That makes sense.

It might be cool to note that these principles define an entire domain of engineering and instruct the design of things like oil pumpjacks or factory arms. A train’s wheel linkage (or “Walschaert’s Valve Gear”), a construction scissor lift, or locking pliers all use the basis of DOF to apply mechanical advantages and broadly create their systems. Yet, this idea can certainly be applied to more figurative contexts.

In our given press-beating scenario, a single defender acts as one single linkage. N = 1. One bar in our system means that our DOF potential is low. There isn’t much complexity involved.

There isn’t much mobility for that player, either. These players make a decision, it’s either “right” or “wrong” depending on the success of their outcome, and the play moves on from there. Simple and quite binary. But each time we expand this abstraction to the field at large, we add more linkages and more connections, boosting N, introducing some restraints, but ultimately driving up the DOF.

If we think of this DOF concept in soccer terms, we can recognize that the more ways in which a defensive unit can move and twist, the larger propensity it has to fail. As attackers, we want the DOF to be high, such that a passing option can’t simply be eliminated with one single “well-behaved linkage” or player. We want defenses to have to commit multiple moving parts to prevent our progression, such that there are more ways in which things can go wrong. A coordinated effort is much harder to orchestrate than the motion of one single component.

(For those that skipped ahead, feel free to return here!).

Imagine a scene in which we’ve got two defenders working in our triangle. In an ideal world, each one would execute their defensive plan perfectly, each positioning themselves to mark the space between our two options, and successfully prevent the blue team from building up.

But while, with one player, it’s easy to simply make the right or wrong decision, two requires perfect execution at two decision-making junctions, and this increases red’s chances of failure.

If only one of the red players fails to use his cover shadow to mark out their corresponding option, as seen in both cases above, we’ve suddenly got a perfect route to solve the problem. Now, even if one red executes their part of the action perfectly, there’s still a chance that the other won’t, and the effort will be beaten. A press is only as good as its weakest link–one “wrong” decision, and it fails.

This is, really, why defense is hard.

One lone talented striker is likely enough to bag your team a fair number of goals. Plenty of sides base their entire strategy around this, largely dependent on one critical cog in their machine. One lone talented defender, on the other hand, is unlikely to be able to stop an onrushing attack. Successful goal-scoring often requires only one moment of brilliance. Resolute goal-prevention is founded on consistency, and requires the whole group to avoid mistakes. The scoreboard doesn’t punish an attacker for making mistakes–the tally remains idle. A mistake on behalf of a defender is instantly broadcast to the entire stadium.

Thus, blue, in the examples outlined above, only needs one faulty seam to break through.

If we outline a diagram, it makes this idea even clearer. The decision tree, below, shows what happens if each defender is equally likely to make a “right” or “wrong” decision. In our 1 defender case, if that single player successfully uses their cover shadow to mark the space between carrier and target, they succeed in stymying the opponent’s build-up. If they falter, however, it fails, and blue will progress. For now, we’ll have this represent a 50/50 situation.

The more players we introduce (for those who read about Gruebler’s Equation, as N increases), the more of these decisions we need to make in any given moment. As mentioned for defense, only a single defect is enough to ruin our system, meaning that even if 3 players make the right call, just one that fails to do so (assuming the carrier is able to pick out the pass) will cause the press to be broken. See the RRRW or RRWR cases in the tree above, as examples.

A 2 defender environment leaves red with only a 25% chance of preventing blue’s progress, while 3 players halves this, and 4 halves it once more to a meager 6.25%–almost ten times less likely than our single defender 50% efficacy case. Such is the power of exponential trends, and why compound interest makes us rich, but more importantly, why increasing complexity increases a system’s propensity to fail by an even greater margin. There are more joints to grease, more bars to bend and break, and the aggregate product is reliant on every component. More parts means we’ll inevitably fall apart more often.

Even if we challenge this notion by saying we just have really good defenders, players that make the “right” decision 90% of the time, the phenomenon still makes a drastic impact on our outcome. A back four means our success rate will be 0.94–or only 66%–in any given moment, compared to a single one of those talented decision makers hitting 90%.

It might feel counterintuitive, but within our decision-making model, the more players the defense involves, the better our chances actually become.

Now, this notion certainly has its caveats. It’s, frankly, pretty jarring to begin with. The fact of the matter is that by introducing more defenders into a certain area, we tend to exhibit this notion of congestion–where the field gets clogged up by just how many players are held within it. This happens when cover shadows overlap, and with sufficient saturation, we end up seeing that one player might actually guard out two targets, or three, dramatically increasing efficiency. It’s really not as simple as we’ve made it out to be!

…and if you thought this, you’d be totally correct. This conversation is nuanced and I’ve actually written an entire article on this very question. Definitely check it out to learn more about what makes increasing or decreasing numbers easier or harder for attacks and defenses. You can do so by clicking the link, below.

For more on why “more defenders” may not be so great after all: Why Inequality is the Key to Unlocking Football

But for now, we ignore the CB’s passing ability, the pre-existing score, each team’s current place in the table, and the field’s congestion, too. The reason triangles, fundamentally, are so powerful, is that they require a much more sophisticated, lower-success-probability structure to defend. They’re also a relatively ubiquitous shape on the field, meaning that they quite organically pop up everywhere, especially given the rise of Juego de Posicion and many modern formations that emphasize the shape’s recognition. Even better, triangles only require only one extra player (over our initial linear 2-attacker model) to earn all of this extra defensive complexity benefit. They’re efficient and destructive to a team hoping to quell a bubbling attack.

Thus, by employing these geometric structures, we can really put the red team in a pickle. Method 2 speaks to the advantage we have, on the ball, in bypassing one defender when they’ve got multiple options to mark. It also shows why even if they have enough resources to mark two, in ideal circumstances, we’d still fancy our chances.

Method 3: An Objective Shift

Our third and final suggested approach is short and sweet: re-adjust our target. Instead of finding a player in a triangle that can then re-route to our original intended target, we simply stop after the first step.

The reason this can be so effective is due to the aggregation of Method 1 and Method 2’s benefits. If we engage a press by finding a target, making it known that we wish to drive the ball there, forcing a team to space-mark, and then happily playing a different route, we use the shoulder cue to delude defending teams seeking to predict the future, while simultaneously using the power of triangles to advance the ball.

Much of these types of moves can be categorized as “shifting the point of attack” or simply displaying patience. We probe up the field, that player attracts markers, and we acquiesce in our circumstances by playing laterally, or a generally different option.

For a moment, here, it’s important to pause to note the innate advantage in playing diagonal balls over horizontal or vertical ones. Horizontal passes switch the point of attack, and cause the defense to shift (perhaps being forced into making mistakes), while vertical balls advance us up the field via sharp probing. A diagonal combines these two utilities–shifting while advancing–and is incredibly powerful. It also can create angles that render vertical or horizontal cover shadows entirely useless. When we employ Method 3, it is often best to find opportunities that allow us to play diagonally. These channels often allow us to arrive at our vertical or horizontal destination, but by re-routing, as seen below.

But we might not always have that option. In the case that we play sideways, for instance, we might reasonably be concerned about this technique stalling our team’s progress if it continues to happen. More fundamentally, if we always resort to our second-best passing option, can we ever truly arrive at our destination? The answer is yes, but for a moment, we can use this fear to reflexively conquer itself.

Method 4: The Meta Method 1 or “Playing God”

What we might now understand, perhaps forging the emergence of a transcendent refinement of Method 1, is that we often cannot give away which player is our true target.

We constantly engage in the art of deception in football, and the greatest trick of all is to find the pass we’d like to play, find a decoy, and use the shoulder cue to suggest that our second option is, in fact, our first. Critically, the distinction here is that we never actually express our intent to travel along the first path. While in our standard method 1, we see an obstructed passing route, suggest we wish to go elsewhere, and then come right back–here, the defender never knows to guard option A from the beginning.

All of this plays out in a matter of mere fractions of a second, but those that are skillfully able to employ it will find that their ideal routes clear up in no-time. The build-up will occur more quickly and more smoothly, too.

This Meta Method 1 tells us to “play God”, in a sense, and encourage teams to aggressively mark players that we simply have no interest in passing to. It’s all about manipulation. It’s pretty amusing to do, too.

After all, the best way to circumvent a carefully executed space-mark isn’t to convince the marker to simply step out of the way, but it’s for that cover shadow to have been obstructing the entirely wrong lane in the first place.

It manifests itself with precisely the same outward actions as the original Method 1, meaning that it’s impossible to detect if players like Xavi, Guti, or other master passers are employing it, even if we know they very likely are. But the truth is that with Method 4, deep inside, we’re never actually resorting to our 2nd best choice, we’re always finding our 1st.

From Twitter user @JoshMoffet17, how Xavi would pick his pass, find a decoy, invite the press, then slot it home

Till next time.

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