We used the PPDA to analyse the different defensive styles of European clubs.
Goals scored, Goal Score Rate, the difference between goals and Expected Goals are all measures suitable to assess the offensive ability of a team. But what about pressing? In a football where defensive styles are evolving and the boundaries between the two phases of the game are fading, the pressing is left out of the parameters of objective analysis, left to subjective interpretations, neglected.
The PPDA or Passes allowed per Defensive Action addresses the need to quantify the intensity of the pressing of each team. It is calculated by dividing the number of passes allowed in the attacking half by the number of defensive actions taken, intended as interceptions, tackles attempted and fouls committed. The resulting number indicates the frequency of a team’s attempts to recover the ball in the early stages of the other team’s build-up, allowing to measure the defensive pressure in an objective and comparable manner.
The greater the offensive pressing brought by a team and the lower the value of the PPDA will be. On the contrary, a team that prefers to defend closer to the goal will have a higher PPDA, resulting from the greater number of passes allowed in the attacking half before attempting to recover the ball.
Defensive styles in Europe
The continuous evolution of modern football, often contrasted by traditional principles, is giving managers the power to go beyond the characteristics of the single league and to give shape to their own vision. By analysing the average PPDA in the top-5 European leagues, we can see how differences in the defensive styles are narrowing, suggesting how the tactical philosophies are expanding beyond the boundaries of a country. La Liga is still the place to be for a manager that prefers an aggressive defensive style — highest PPDA — even if the differences between the leagues are at this point subtle, with only two passes separating La Liga from the Bundesliga, with Ligue 1, Serie A and Premier League performing within the range defined by the Spanish and German leagues.
The situation changes when considering the variability within every single country. In this sense, La Liga is again the most consistent one in terms of press intensity — variance equal to 3.58 — confirming how Spanish clubs, with their playing style, haven’t quite suffered the influences of modern football and have rather shaped it on their own terms.
Despite evidence from the past suggests a decrease in the variance as the season progresses, the Bundesliga trend signals a strong and extensive change that goes beyond seasonality. The mother of gegenpressing comes last for both press intensity (12.13 average PPDA) and consistency showing the highest variability between the different clubs in terms of defensive style(variance equal to 7.74), in sharp contrast with the values of the last season where Bundesliga was the second most consistent league in terms of press intensity (variance of 2.32).
An era of evolution
An explanation for the change affecting the German clubs can be found in the number of new managers that stepped in between the end of the last season (see Labbadia at Wolfsburg) and the beginning of the new one (see Weinzierl at Stuttgart). If the appointment of Rangnick as the manager of RB Leipzig can be considered just as a temporary role while waiting for Neigelsmann, the arrival of Favre at Dortmund has had an effective impact on the club’s philosophy. The Swiss manager began his adventure in the German territory with a bold step. He put aside the belief that had distinguished Borussia Dortmund since the Klopp’s era, an aggressive pressing style that in the last years had turned into an ineffective attempt to remain faithful to the original principles, and replaced it with a more conservative approach — PPDA up from 7.48 to 12.16 — that is so far paying dividends both in Bundesliga and Champions League.
In Premier League the different defensive styles are the result of an ongoing clash between the traditional English football and the influx of ideas, sometimes experimental, evolved over the time thanks to the competition between some of the best managers in the world, attracted by the lights of the richest football league. Pochettino first — since his time at Southampton — was a precursor in bringing an aggressive defensive style to the Premier League (Southampton had a PPDA equal to 9 in 2012/2014). His Tottenham is today the second team, after Emery’s Arsenal, for press intensity — PPDA of 8.6 for Arsenal, 9.3 for the Spurs — leaving behind Manchester City — PPDA equal to 9.8 for the skyblues — and the new Chelsea, transformed by Sarri, and whose PPDA has dropped radically from 12.3 to 9.6, becoming the third team in the Premier League for high-pressing intensity.
Once forerunners of the aggressive pressing style, both Guardiola and Klopp seem to be on their way to a more conservative approach. In the last two years, Liverpool has moved from 7.2 PPDA to 11.5 while City, after the first 16 games of Premier League, has an average of 9.8 PPDA, up from the 6.4 of the last season. Both Guardiola’s and Klopp‘s trends show how they have gradually moved to a more prudential, less obsessive pressing style. Liverpool and City are nowadays turned into teams able to better manage the timing of their pressing, more aware of the importance of adapting their defensive styles to the different moments of the match and to a Premier League increasingly characterized by teams able to manage with quality the early stages of the build-up.
In Serie A the change is shaped by the revolutions brought by Ancelotti and De Zerby as well as by the need for Roma and Milan to adapt to technical and medical issues. Ancelotti’s work has brought Napoli into a new era. He knew he needed to radically change the team’s playing beliefs to invigorate players exhausted by three years spent chasing unsuccessfully Juventus and he did it by giving his Napoli a more conservative defensive style — from 9.5 to 11 PPDA — and a fast and continuous verticalization. Different managers, different styles. From a manager that prefers a low-intensity pressing, there is another one that has made the aggressive recovery of the ball as the critical point of his football. Under De Zerbi’s guidance, Sassuolo has become one of the teams with the highest intensity of pressing in Serie A (from 12.1 to 9.6 PPDA), proving how the strength of powerful ideas goes beyond the limits defined by a club’s history, profile or ranking.
With the likes of Nainggolan, Strootman and Alisson as a keeper, Roma was once a team ready to face the enemy, to fight aggressively to recover the ball. The departures of three of the most important leaders in the Roma’s locker room have deeply changed the team’s attitude. From being the second team with the highest press intensity in Serie A last season — 8.6 PPDA — Roma now shares the tenth place with Empoli and Cagliari — 11.2 PPDA — a change that suggests how Di Francesco’s team has lost the confidence to defend 40 yards away from the goal. On the Rossoneri’s side, the high number of injuries has forced Gattuso to adopt an even more conservative approach in their defensive style, relegating Milan to the five to last position — 13.4 PPDA — for press intensity in Serie A.
The idea that a team’s performance is the main factor determining that team’s defensive style is questioned by the weak correlation — r² of 0.183 — between a league’s rankings and the intensity of pressing.
On the contrary, the influences of international coaches and the strength of their beliefs seem to have a decisive impact on the defensive styles of European football clubs. The liberalisation of the labor market after Bosman ruling has brought to a continuous flux of styles and innovations that are blurring the boundaries between the leagues and questioning the solidity of traditional principles. It is then more likely to find similarities between Eibar and PSG — the two teams with the highest press intensity in the top 5 leagues — or between the Spanish Atletico Madrid and English Leicester— 10.7 PPDA for the Colchoneros, 10.9 for the Foxes — rather than between Simeone’s team and Betis Siviglia — 6.9 PPDA — proving how managers have an ever-growing influence on their team’s tactical approach.
There are nowadays clear patterns of play, both offensively and defensively, that go beyond the limits defined by the local traditions and that define horizontal segments including teams of different size, quality and origin.
PPDA can be used as a tool to compare different clubs, leagues end managers providing an objective snapshot of a team’s defensive style. It allows to monitor its evolution over time and to analyse its adaptation according to the opposition's attacking approach.
The large variety encountered between the different clubs, in terms of PPDA, suggests how European football is becoming a battle between different ideologies that constantly grows in complexity. It highlights a strong diversity in the defensive styles across Europe and underlines how the strength of managers’ ideas is becoming every day more powerful in shaping characteristics and defensive attitudes in modern football.
¹ The variance measures the dispersion of the distribution around the mean, in this case, it measures how far clubs’ PPDA are spread out from the average PPDA.
Data from Understat