Although as coaches we (should) always consider progressions into our session plans, are we always thinking these through as much as we should? Could we use a systematic approach to make sure we are meeting the players’ needs?

The importance of differentiating between difficulty and complexity

When coaches discuss progressions in their training sessions, they often think of it as “how can we make this game more difficult for the players?”, but rarely “how can we make this game more complex?”. What might seem like a simple semantic question is actually essential to get what we really want out of a session.

Simply put, difficulty is the amount of effort the players must use to compete in a game while complexity is the level of thinking required from them ¹. It is therefore clear that the stimulation is different whether a task is difficult or complex.

As a tool for mathematics teachers, John Hattie suggests a difficulty and complexity matrix ² that can help teachers to assigned appropriate learning tasks to their students. It is a simple coordinate graph, with the horizontal axis representing the level of difficulty, and the vertical axis the level of complexity.

The matrix identifies four main relationships between difficulty and complexity. A fluency task will be learnt and then executed automatically, therefore being quite easy (low difficulty) and simple (low complexity). A stamina task can be viewed as a problem requiring to complete an addition of fluency tasks, hence increasing the amount of effort needed, and therefore the level of difficulty, while remaining simple. It can also be determined by the number of people able to solve the problem i.e. if only a few people are to solve this equation, it can be deemed as difficult. Strategic thinking intervenes in the context of a contextual problem i.e. a problem-solving situation that can be solved by using the appropriate knowledge. Finally, the expertise level requires the student to use his knowledge in a new way to come with an unique and personal answer.

Although the above examples are based on mathematics, we can try to apply this matrix to football.

To begin, we can differentiate the execution process in the lower half of the matrix, from the decision process in the upper half. The difference between the two is the cognitive load required to perform a task. Executing even a very difficult technical movement doesn’t necessarily requires a high level of thinking.

We can then split the matrix in four quadrants as per John Hattie’s.

The bottom-left will be the initial stage where a player learns a new technique, with very low to no cognitive stimuli, to focus exclusively on the execution. The player can then progress on the difficulty scale towards the mastery of the technique. Obviously, not all players will be able to reach mastery, and some will peak before this stage.

Problem-solving will be the point where high complexity and low difficulty meet. This is the part where players are in situations testing their understanding of the game. The amount of effort required to succeed is low, but the level of thinking is very high. Finally, when complexity and difficulty meet, the player will need to be creative to solve the problems he’s facing. Creativity here is used in its broader sense, not only limited to creativity on the ball. A defensive action can be creative as well in the sense that a player or group of player can make original decisions to react to a situation.

Let’s take a few examples to illustrate and understand better each of these stages.

When planning games for a session, it’s essential to know what we want to focus on primarily. With young players, or players new to football, we might want to improve the execution more than the decision making in a first place. Training sessions should then follow in priority an horizontal progression on our matrix, to help the players reaching technical mastery. This obviously doesn’t mean that complexity in games should be completely removed. For example, a group of Under 10 should, of course, play small-sided games at training. However, inside the game, the coach might ask the players to use only their other foot (or weaker foot), making it more difficult but maintaining the complexity level.

With older age groups, however, the sessions should become more decision-making orientated since players should already be comfortable with difficult tasks. To use the previous example, there would be little benefice asking a professional player to use only his weaker foot during a game. The coach should instead challenge the players with cognitive tasks. For example, in a game, asking the team in possession to constantly create numerical superiority around the ball to progress on the pitch would be complex.

Using the matrix in a constraint-led approach

Football coaches should be, consciously or not, familiar with the constraint-led approach. I will not go into too much details here because it is a topic of discussion of its own, and there are more qualified people who have already written very instructive articles about it ³. In summary, a constraint-led approach is the manipulation of certain elements of the game to guide the players towards specific learning outcomes. A constraint in this context is not necessarily a restriction, it can and should also take the form of an incentive. As an example, instead of only allowing a goal to be scored after 5 passes are made within the team, the coach can give an additional point if the team scores after making at least 5 passes. Although the outcome sought by the coach remains the same, the way the players will get there is different.

Using the matrix we just discussed, we are going to see how we can come with a system to help us setting up the relevant constraints in our games.

Constraints can be classified in 3 categories depending on the element they affect:

1. Player – These are specific to the individual. Typically, the genetic attributes, the emotional state, the behaviour, the ability to learn… These can’t hardly be manipulated by the coach but must be taken into consideration.
2. Environment – It is the general surrounding of the learning place. It includes elements like the weather, the playing surface, the training time/day… but it also includes the socio-cultural aspect such as the personal situation, the culture of the player, the culture of the club… Some of these can be manipulated by the coach, some can’t be.
3. Task – These are the rules of a game, the dimensions/shape of the playing area, the equipment used, the scoring system… All of them can be manipulated by the coach to affect the player-environment interaction.

Each time we manipulate one or more elements of these categories, we affect the way the player is going to act and learn. Some constraints might impact more the execution process, some the decision process. Coaches therefore need to be conscious of which process they want to impact more in a specific game, and use the appropriate constraints to reach this objective. To help us setting the right constraints in a game, I have tried to come with a system to monitor the level of difficulty and complexity we are proposing to the players.

To begin with, I have tried to classify a list of constraints into different categories depending on whether they would affect the difficulty or the complexity of a game. These are my personal views, and other coaches might have different perceptions. This is only a suggested framework which might need to be personalised.

Difficulty constraints:

• Numerical balance: whether there are any neutral players in a game, or whether one team has a numerical advantage over the other team. Having an overload in possession will obviously be easier than playing with even numbers or an underload.
• Playing area: the area can be adjusted to be either bigger or smaller. The appreciation will depend on the number of players involved in the game. For example, a 40×30 yards pitch to play a 5v5 game will be considered as normal since it is the standard size for this format. If you were to play the same game on a 30×20 yards pitch, the playing area would be considered small. In possession, the smallest the area, the more difficult it is to execute a task. And it is the opposite out of possession.
• Number of touches: the touches on the ball can be unlimited, conditioned or limited. Unlimited or limited constraints will apply to the whole playing area without conditions or players’ distinctions. Conditioned constraints might apply to specific zones of the playing area, or certain situations only (first touch finish, unlimited in defensive third but ‘x’ touches in attacking third…). Limited touches will typically be more difficult as it would usually be a 1 or 2 touches game.
• Physical stimuli: some constraints can affect the physical demand of a game. For example, allowing players to use their other foot only, or as Tuchel made it popular, asking defensive players to hold a tennis ball in each hand while training set pieces, to prevent them from grabbing their opponent’s shirt.
• Environmental stimuli: these constraints can either be manipulated or they are forced. If it’s raining heavily on the day of a session, we know it’s going to be more difficult for the players as the rain will have an affect on the condition of the pitch, the players’ comfort,… Although we can’t control these constraints, we should take them into account as they will impact the difficulty of the session. Some environmental constraints we can control would be for example to be a bias referee in a game, not using bibs to differentiate teams…

Complexity constraints:

• Type of game: games can be constant, variable or random, from the least to the most complex. In a constant game, a same skill is repeated in the same condition. In a variable game, a same skill is repeated in different situations. In a random game, different skills are performed in unpredictable situations.
• Freedom of movement: players’ movements across the playing area might be constrained. They can be locked inside a specific area, or conditioned to travel from one area to another, or finally they can be totally free. The more freedom the players have, the more complex it will be, since it will increase the number of decisions they have to make.
• Scale of the team: a game can focus on different part of the team. The simplest one will be at the individual level. More complex, it will focus on a group of players (3 or 4) or a unit (defence, midfield or forwards). Finally, the most complex will be units or at the whole team level. Systems, positions and lines require more thinking from the players as there will face a wider range of situations and will need to make decisions based on more factors at the same time (self, team mates, opponents, space, the ball).
• Topic of the game: sessions should be built around the principles of play, and these can either be macro principles, sub-principles, or sub-subprinciples. The macro level is the most complex as it also includes all the micro principles. For example, if the topic of a game is the macro attacking principle of progressing through the thirds, it will be a complex task for the players because they will have a number of problems to solve and therefore a lot of decisions to make: how to keep possession, when to play forward, what type of passes to make… However, if we were to break down this principle into smaller pieces and focus only on one sub-subprinciple such as creating width and depth for example, the players’ decision making process would mainly be concentrated on this topic, reducing considerably the number of problems to solve.
• Cognitive stimuli: it is possible to add some extra stimuli in a game to increase its cognitive load. The shape of the playing area can be modified (circle, hexagon, triangle…), the number, size and/or positioning of the goals can vary…

I have then summarised the categories and related constraints into the below tables. Although the complexity constraints’ categorisation won’t differ depending on the moment of the game we train, the difficulty one will need to be adapted. The below will apply to the possession and attacking transition phases. However, the numerical balance, number of touches and playing area will need to be inverted for the defensive transition and out of possession phases.

When designing a game, we can use these tables to measure its levels of difficulty and complexity to ensure it is in phase with the outcome we are targeting. Simple/easy constraints will be rated 1, medium 2 and difficult/complex 3. We can then rate each component of the game and come with difficulty and complexity average ratings.

Practical examples

Let’s see how a training program could be built, and how we could use the difficulty and complexity matrix to help us planning and monitoring our sessions.

Inspired by the tactical periodization methodology ⁴, I would base my training program upon my game model. Each session would be built around the acquisition of a principle of play. The first session would be of a low difficulty to help the players understanding the principle first. During a session though, the complexity level needs to constantly increase. Over the course of a season, the players will have multiple sessions on a same principle, but the difficulty will increase as their understanding of the principle improve.

As an example, if one of my attacking principle is, as mentioned previously, progressing through the thirds, I might start training one of its sub-subprinciple which could be third-man combinations. Here are 3 games we could do in a session, with a constant complex progression while maintaining a low difficulty level.

Using the matrix, the game seems to be fairly easy and simple:

The next game would then increase the complexity:

The players are now allowed to move across the pitch under certain conditions, making the game more complex. To make it more realistic and allow the players to make their own decisions, we add an incentive rather than a restriction (3 points for a goal after a third man combination). This is also the occasion for the coach to check the understanding of the players.

Finally, we would put the players into a small-sided game, increasing the complexity to its highest level, but still maintaining the difficulty level as low as possible to allow the players to focus on their understanding of the principle and their decision-making.

Players now have positions and roles in the game, as well as total freedom to move on the pitch.

Depending on the players’ acquisition of the principle, we would then train the same topic again later in the season, increasing again the difficulty of the sessions as well to develop the players’ ability to apply the principle in more difficult situations. As an example, we could use the same small-sided game but increase its difficulty:

This game is more difficult as the 2 neutral players have been removed, and it is now 7v7 instead of 6v6 in the same area. We have also added some conditions to the touches allowed.

In the last progression, we’ll remove all neutral and supporting players, playing a 9v9 in the same area as previously, with only 2 touches allowed per player.

Takeaways

In a recent interview ⁵, Borussia Monchengladbach’s assistant coach Rene Maric stated that “Sometimes, a player realises he needs to be four metres to the left to close a gap and by that simple act, he solves a problem for his team and creates a new one for the opposition. There are infinite decisions made in a game of football. It’s impossible for the coach to make this decisions for the players. We can give them a guideline or a “solution space” through principles, they have to perceive, decide and execute on the pitch.“

As coaches, we must make sure we are developing the players’ cognitive ability as much as we develop their technical, tactical and physical skills. Training sessions should therefore be planned and designed to achieve this objective, giving the players some guiding principles but encouraging them to solve problems on their own. Unconsciously though, we might be sometimes focusing too much on the player’s execution in training sessions, and not enough on the thinking process behind a movement. Making a clear distinction between decision and execution tasks might therefore be helpful. Coaches might have different views on this topic though, and this method is an example only. It might not work for everyone, or might need some alterations, but more importantly this might help some coaches to reflect on and improve their training methodology.

References:

1 David A. Sousa (2011) - How the brain learns
2 John Hattie (2008) - Visible Learning for Mathematics
3 https://medium.com/my-fastest-mile/constraints-player-development-in-football-748bdbb97441 and https://drowningintheshallow.wordpress.com/2016/03/14/what-is-a-constraints-led-approach/
4 X. Tamarit - What is tactical periodization? / J-L Delgado-Bordonau & A. Mendez-Villanueva - Tactical periodization, a new soccer training approach / J. Guilherme Oliveira - Tactical periodization, Theory & Fundamentals
5 https://theathletic.co.uk/1669125/2020/03/16/rene-maric-borussia-monchengladbach/

Session’s objectives

• Encourage a team to press high and regain possession early
• Develop confidence and bravery out of possession
• Demonstrate the importance of playing at high intensity
• Encourage team work

Coaching points

On the ball:

• Identify and react to pressing triggers
• When pressing, runs MUST be at 100% pace
• Body shape to show the player wide

Around the ball:

• Mark players directly around the ball carrier to block short passes

Away from the ball:

• Get closer to the your teammates to restrict space
• Anticipate long balls/switch of play

Practice 1: Possession game

Organisation:

Pitch size depending on numbers and abilities. Increase the size if players find it too easy.

4v4+4 – 2 target players outside the pitch at opposite ends and 2 jokers in the middle playing with the team in possession. Target players can be pressed.

Rules:

Team in possession try to pass the ball from one target player to the other without being intercepted.

Team in possession can use both jokers.

All passes must be on the ground.

Target players can’t pass the ball to each other.

Scoring system:

In possession: 1 point for linking up both target players in a same possession phase.

Out of possession: 1 point for winning possession and passing the ball to a target player before the other team can either make 3 passes or link up the target players.

Coaching points:

• When to press? On any of the pressing triggers (soft pass, back-pass, poor first touch…), on the time of the pass to be as close as possible to the receiver on his first touch
• How to press? At full pace, slow down just before the receiver’s first touch, body shape to force the player into one direction
• How to support? Quick support, anticipate next pass based on teammate’s body shape, compress the area around the ball to block short passes

Practice 2: 5v5 directional game

Organisation:

A pitch 40x30m split in 2 halves

5v5+2

Rules:

Directional game – Team in possession scores by passing the ball to the target player defended by the other team (here, reds attack from left to right).

Team in possession can only score by passing from inside the target player’s half.

Target players can be pressed and tackled.

No offsides but all passes must be on the ground.

Scoring system:

Team in possession:

1 point for a pass to the target player

Team out of possession:

1 point for winning the ball in the target player’s feet

2 points for winning the ball in the other team’s half and completing a pass to their target player or making 3 passes

Coaching points:

• Know when to press – Identify pressing triggers. If the situation doesn’t allow press, hold positions to prevent forward play
• Press at pace – High intensity to close the receiver down as quickly as possible
• Force wide play – Body shape to force the opponent wide, curved runs to block central passes
• Quick support – React quickly to teammates movements to overload the area around the ball and restrict space to the ball carrier
• Balance – Player on the weak side tuck in to maintain compactness

Situations to coach:

Here are a few situations likely to happen during the game, which can give the opportunity for the coach to intervene and reinforce the coaching points.

• Ball in target player’s feet

#9: Do not press the target player unless you have close support to block short passes options. It is too easy here for the target player to pass the player even under pressure. Instead, wait for him to make a decision, and press on the time of the pass.

• Pass to the centre-back

#9: Curve your run to prevent switch of play and force the CB to play wide

• Winger drops to support CB

#11: Quick support when the CB is forced to play wide, mark your man to prevent short pass

• Cover

#8: Cover your teammates, block the space between #10 and #11 to prevent through ball and overload the area

• Balance

#7: On the weak side, tuck in to maintain compactness and anticipate a long ball

The team should be able to create the below situation:

Practice 3: Phase of play

Organisation:

Half a pitch

One goal and 3 gates

5v6+GK

Rules:

Red Team defends the goal and score by dribbling through one of the 3 gates

Blue Team tries to win the ball and score

Every time the ball goes off the pitch, the play restarts from the GK with a goal kick

Scoring system:

Red Team

1 point for dribbling through an orange gate

3 points for dribbling through the red gate

1 point every 5 passes completed

Blue Team

1 point for a goal

3 points for scoring a goal after regaining possession before the Red Team has completed 5 passes

Coaching points:

• Triggers – Identify the triggers and react quickly
• Force wide play – Isolate the ball carrier to restrict his options with the ball
• Compactness – The whole team must press together to remain compact and prevent play through the central channel
• Intensity and aggression – When the pressing is engaged, players around the ball must press at full pace and challenge the opponents with aggression

Here I will then suggest a training session focused on running behind the defensive line. It will involve 4 practices, based on a squad of 16 players.

Session’s introduction

To introduce the topic, I like to start with a little game. This one is very simple. It is played with the hands on a pitch longer than wide. The size will mostly depend on the age group, but 45m x 35m is fine for U18 upwards. There should be a light warm-up before starting though as this will involve accelerations.

The pitch includes 2 end zones, about 10 metres deep and on the whole width, where teams can score points. We’ll play for 10 minutes.

To score a point, a player must receive a pass in the end zone, but can’t enter the zone before a pass is made. Same rule applies for the defending team to block a pass. Players are allowed to run with the ball, but possession turns over if the ball carrier is tagged.

To progress this game, you can forbid back-passes to encourage forward runs. You can also only allow passes below the chest to encourage players to create clear passing lines.

There is no coaching in this game, the aim is to let the game introduce the topic.

Constant practice

We would then go into an unopposed technical practice, for about 20 minutes (6 minutes per variation and 2 minutes break). This practice will set the base for the rest of the session, introducing different variations of forward runs behind a defensive line. This will also allow players to work on their passing and receiving technique. The set up is as shown on the below picture. If you don’t have mannequins, I usually use 3 cones placed in a triangle shape, to represent an opponent. The ball can’t go through the cones. You need a minimum of 7 players.

Players will work on different variations:

• Straight run outside the defender
• Curved run outside the defender to receive in a different channel
• Wall pass and forward run between 2 defenders

Coaching points for the wide players (C and F) are:

• Movement: Go-to-show to create space
• Communication: Make eye contact, verbal or non-verbal communication with passer
• Timing of runs: Time your run to avoid being offside
• Change of pace: Acceleration needs to be brutal

It’s important to insist and get the players to make a dummy run before their forward runs. In match situation, this movement will often drag the defender and give a considerable edge to the attacker. It’s also a way to avoid being offside, as it gives the attacker some extra space before reaching the offside line, and the passer a second or 2 to execute his pass.

For players A, B, E and D:

• Weight of pass: Passes need to be whipped to switch the play quickly and change the angle of pass
• Body shape: Side-on to be able to receive to play forward
• First touch: With the inside of the foot, forward to pass the ball on the second touch

Note that between variation 1 and 2, players in B and E should adjust their first touch to have the appropriate angle to play forward. In the 1st variation, the wide player wants the ball through the closest channel, therefore B and E should take their first touch slightly towards the centre of the pitch. In the 2nd variation, the wide player wants the ball in the far-side channel, so the touch should be forward towards this space.

Function practice

In the same area, we replace the mannequins by defenders and draw a halfway line. A team of 4+GK will play against the 3 defenders. We add another goal and a GK at the other end of the pitch. The practice will last about 25 minutes, split in 5 sequences of 4 minutes to allow rest and have a high intensity during the practice.

The play always restart from the GK if the ball goes out. Passes are only played on the ground. The defending team can only defend in the other team’s half, and offsides apply from the halfway line. When an attacking player receive the ball in the other half, he plays a 1v1 with the GK. The attacking team get a point for a goal, the defending team 2 points. This will encourage the defending team to press.

In this game, we should encourage the centre-backs to move the ball quickly at the back to find the right angle to play forward. It will also move the player pressing them and open gaps in the unit. As in the technical practice, we should ask the CBs to play diagonal forward passes rather than straight ones. This is much more difficult for the other team to defend, and it is easier for the receiver to play forward when the ball comes from in an angle rather than from behind.

There are lots of decision making and problems to solve in this game: when is the right time to play forward? What type of forward run should I make? How can we create gaps in the defensive team?

To progress, you can allow one defender at a time to defend in his own half. In this configuration, you can introduce to the players the idea of dummy forward runs to create space behind. Players will also need to identify when they can use a teammate’s run to their advantage. In this progression, you can also allow the player on the ball to dribble forward to enter the attacking half. It will reward even more the players making the runs, and force the defenders to make more decisions.

Phase of play

In the last practice, we play on roughly 3 quarter of a pitch, with the halfway line as the offside line. The attacking team will have an overload to get more success, so the teams are 9v7 with a GK in each team.

We play with no corners to keep the game going and get as many situations as possible. The play restarts from the attacking team’s GK if the ball goes out for a corner. Equally, if the defending team’s GK get the ball, play restarts from the other GK.

To start, the defending team can’t enter its own half, this will give more success to the attacking team. If the defending team manages to regain possession too quickly and keep the ball for too long, you can restrict their number of touches, and split the half in 2 or 3 zones, with players locked in specific zones.

Here, the attacking team (blues) is set up in a 2-3-3 to replicate a 4-3-3 formation, but it should be adjusted depending on the team’s shape in matches.

In this game, players can play long balls off the ground as it should be game realistic. However, we should encourage passes on the ground as much as possible to make the play as quick as possible. This will be important when we progress the game and that defenders are allowed in their half. In this progression, like in the previous practice, we should encourage players to make multiple forward runs even if they don’t receive the ball, as it will create space for teammates. You can add the same rule as previously (ball carrier allowed to dribble in the other half).