It’s easy to measure the attacking output of a team or an individual player in any sport. We have a defined target we can move towards and analytics gives us the power to dive deep and analyse the numbers at a granular level.
I have already covered the power of Expected Goals (xG) and Shot Creating Actions (SCA) and Goal Creating Actions (GCA), and Post-Shot Expected Goals previously. These metrics help us understand how good a player is going forward, how lethal or accurate he is based on the kind of opportunities he gets and how creative a player can be. It’s easy to calculate all of these stats because analytics is geared towards breaking down attacking situations.
What about the defensive side of the game, though? How do you measure how well a team defends, from front to back? Specifically, I want to analyze how well a team presses the opposition – a key aspect of modern football tactics.
Most elite teams these days rely heavily on pressing the opposition to win the ball back. So in this piece, I am going to talk about a metric introduced by Colin Trainor here – called Passes Per Defensive Action (PPDA). I found this to be quite an intriguing metric to measure pressing and all credit to Mr. Trainor for coming up with this.
We’ll use the concept of PPDA to look at the top four leagues in Europe and see how the pressing game varies from league to league. Let’s dig in!
What are Passes Per Defensive Action (PPDA)?
Let’s understand what PPDA is before we get into the visualization and comparison sections for each league. Here’s the issue with the traditional defensive stats in football – at an individual level, they can be quite misleading. We typically look at these metrics in silos:
- Blocked shots or passes
- Aerial duels
- Dribbles stopped
- Fouls, among others
These are nice to look at and easy to understand, I get that. But they tell us next to nothing about the style of play of the player or the team. Here’s a classic example from the fine folks at WhoScored.com:
Focus on the last two metrics – Tackles and Interceptions per Game. This is an easy comparison to make, right? But what does this tell us about each team? Is Gerrard making more interceptions because Liverpool used to give up the ball a lot? Where on the pitch is Gerrard making these tackles and interceptions? What I’m getting at here is that this is not a good comparison to make without understanding the context of each team’s playing style.
This is where the Passes Per Defensive Action (PPDA) metric comes in handy. Introduced by Colin Trainor, PPDA “measures the pressure that the defending team puts on the opposition players when they are in possession of the ball”. So instead of using 10 different metrics to understand how a press works, we have one single number to compare the pressing style of teams across leagues. PPDA was introduced in 2017 and has become quite a complex metric with a ton of variables behind it. But for the scope of this article, the four primary things PPDA measures are:
- Challenges (failed tackles)
Whether the press was successful or not is not the aim here. The idea is to measure the pressure a team applies, as I mentioned above. I believe this really helps in understanding the defensive intensity of each team. And with more and more elite teams preferring the ‘high press’, PPDA will take on much more significance as we move forward. It’s definitely a metric to keep an eye on.
It’s a straightforward formula:
PPDA = Number of passes made by the attacking team / Number of defensive actions
The small the PPDA value, the more intense the press. That intuitively makes sense – this means the team making the press has allowed only a small number of uncontested passes to be made.
In this article, we will use Passes per Defensive Action ONLY in the attacking half. While this is certainly debatable, I feel this represents the idea of measuring the ‘high press’ pretty well. You won’t be performing a high press in your own half, right?
With that context, let’s dive into the numbers for the top four European leagues!
Measuring the High Press in the Premier League
Without any further ado, here’s the pressing intensity visualization for 2019/20:
First off, not a lot of surprises. The top teams are essentially the ones who press a lot. Leicester, Manchester City, Liverpool and Chelsea are in the top 5. What I found interesting was Southampton and Brighton being right up there. Ralph Hassenhuttl has done an excellent job with the limited resources at Southampton and led by the tireless Shane Long and Mario Lemina, they sure do employ a strong high press. Brighton under Graham Potter have been the team to watch for sure, even though they trailed off before the season stopped. The intensity of their press might have something to do with the exhaustion that inevitably settles in, especially if you’re not ready for a gruelling season.
Spurs are the ones I want to point out here. For the last 4 seasons under Pochettino, they were top 3 in the PPDA metric. They have dropped off sensationally this season, which explains their drastic fall from grace and Pochettino’s departure. Jose Mourinho is not the biggest fan of the high press so it’s unlikely we’ll see them climb up this table anytime soon.
Newcastle United are a bit hopeless in terms of employing a high press. Steve Bruce knows his team’s limits and is happy enough to concede possession to the opposition and sit back. Their PPDA number is ridiculously high. Talk about outliers, eh?
Measuring the High Press in La Liga
Not a lot of surprises here either:
Getafe and Sevilla, for anyone who has seen them this season, are insane in their pressing intensity. They barely give you time on the ball, let alone settle and pass it around. They surround you like a pack of dogs who get a sniff of fear – and their PPDA numbers reflect that. It’s no surprise that Sevilla are 3rd and Getafe are 5th this season.
Barcelona and Real Madrid are above average in their PPDA numbers but well below what you might expect from an elite pressing team. Real under Zidane have honestly never been a high pressing side anyway, so this isn’t surprising.
What I found really concerning was Valencia, right there at the bottom. Under their previous manager Marcelino, Valencia were known for their pressing intensity, hounding the opposition into turning the ball over. That was a key reason behind their rise in recent seasons from the brink of collapse. They have completely let that go this season and are content in sitting back behind the ball and hitting the opposition on counter-attacks.
Measuring the High Press in the Bundesliga
The Bundesliga is the leader in using analytics to enhance and devise match tactics and strategy. I love the variation here:
Who’s surprised to see Bayern Munich at the top? Absolutely no one, I’d reckon. They have found their groove under Hans-Dieter Flick this season and the swagger with which they press and win the ball back smacks of an elite pressing team. They are a joy to watch if you’re not playing against them.
I was a bit surprised to see Leipzig sixth given their dedication to pressing under Julian Nagelsmann.
I find this visualization quite fascinating given that the consensus among fans is that the Bundesliga is the league with the most High Presses we’ve seen. Both La Liga and the Premier League seem to have a better PPDA than the German top division – a curious insight.
Measuring the High Press in Serie A
All hail Atalanta and….Bologna?
Atalanta are box office right now. If you haven’t watched them play yet, you’re missing out. They are a joy to watch and are absolutely ripping up the attacking side of the game. Their advanced stats are the highest in Serie A, not even Juventus can touch their prowess right now. And employing a high press is a huge part of their strategy (as the above chart shows).
Internazionale under Antonio Conte have also transformed themselves into a pressing unit. I fully expect them to rise up the PPDA rankings next season as Conte has a lot of time on his hands to drill the importance of the high press into him team.
I found the case of Lazio curious here. They’re sitting second in Serie A right now, just a point behind Juventus. They are fourth from bottom in the PPDA metric, suggesting that Simeone Inzaghi does not like his team pressing up. He prefers sitting back, absorbing the pressure and hitting swiftly on the counter (a tactic that has seen Ciro Immobile leading the scoring charts). They are thrilling watch when they go forward.
This isn’t a perfect metric by any means. There’s a lot it still doesn’t capture and it definitely shouldn’t be taken as the only metric to understand a team’s style. New metrics are emerging such as aggression (measures the ability of a team/player to press within 2 seconds of the opposition completing a pass).
However, PPDA does give us a good insight into how a team approaches the pressing aspect of the game. I would love to hear your thoughts on PPDA, what insights you took away from the visualisations, and what aspects you would want to analyze to measure pressing.