This is the third blog in a three-part series examining Liverpool’s injuries this season. The first investigated the direct impact of injuries on Liverpool’s squad; the second analysed the repercussions for Liverpool’s attack; and the third is a comparative piece looking into whether Liverpool’s injuries are (not as bad as / equal to / worse than) their main competitor’s, Manchester City.
METHODOLOGY
For this comparison, I will be focusing on the first 28 Premier League games of the 2019-20 season for Manchester City and the 2020-21 season for Liverpool. This is to allow for direct comparisons between the data and teams. Plus, drawing the line before Matchday 29 has the added benefit of finishing just before the Premier League was suspended last season amidst growing concerns over the coronavirus pandemic, which would skew the data because of the 3-month break between games. These particular seasons were chosen as they represent the worst points tallies for either team over the past four years.
The key factors to analyse were the injury scores for both teams (as a collective, but also on an individual level), as well as the effect these injuries had on the make-up of each team’s starting XI. Relevant players are those who played at least one minute or more during the analysed season, although there were two exceptions:
- Second and third choice goalkeepers were included as long as they featured on the bench on two or more occasions
- A player who had spent the entirety of the analysed season injured (thus playing zero minutes) but had played at least one minute or more in the previous season was also included
The data was collected from one source (Transfermarkt) to allow for a consistent comparison.
OVERVIEW
Below is a graph showing the cumulative points tallies for Manchester City and Liverpool throughout the first 28 Premier League games of their respective seasons:
What the graph shows is that while both teams fared similarly across the first 16 games of the season, from the New Year onwards there was a strong divergence. Manchester City maintained their form to finish on 57 points from 28 matches (2.04 points per game) whereas Liverpool faltered, accumulating just 43 points from 28 matches (1.54 points per game).
Yet both of these tallies represent a drop-off from previous seasons. In Manchester City’s case, the Citizens had 11 fewer points than at the same point during their Premier League winning season in 2018-19. For Liverpool, they were 36 points down on their championship winning form in 2019-20. As was highlighted in my previous piece, Jurgen Klopp’s side has been plagued with injuries. But did a similar situation occur for Man City and how does this compare to the Reds?
HOW MANY INJURIES DID EACH TEAM HAVE?
Below is a table detailing the breakdown of minutes missed to injury (full games only) by both squads during their respective seasons:
Players with no injuries (as recorded by Transfermarkt) are highlighted in green, while a darker red connotes missing 50+% of the season to injury.
What it shows is that Liverpool had more players sidelined with injury than Manchester City, missing 163 matches in total compared to 107. Even factoring in the differing squad sizes still puts Jurgen Klopp’s side on top, with a player missing on average 20.8% of the season compared to 15.9% for Pep Guardiola’s men.
Liverpool also beat Manchester City in terms of how severe their injuries tended to be. Below is a graph detailing the severity of the injuries suffered by both teams:
While Man City had the most serious injury through Leroy Sane, who missed all 28 games due to an anterior cruciate ligament rupture suffered in his right knee before the season began, the majority of their injuries were minor. In comparison, Liverpool has had a higher concentration of medium to serious injuries that has led to lengthy spells on the sidelines for a whole host of their players.
WHERE WERE THESE INJURIES CONCENTRATED?
In a previous piece, I argued that not all injuries are equal. Their impact on a team is due to a variety of factors, one of which is importance to / involvement in the team. However, another key factor concerns which position those injuries occur in. If you have a concentration of injuries in one position, this will cause a greater effect than if the injuries were spread out across positions.
Below is a gantt chart detailing a player overview for Manchester City. Not only does it show who started, came off and came on during a match, but also who was an unused substitute and who missed the match due to injury or another reason.
Here is the same chart for Liverpool:
In both teams, we can see that the injuries were most concentrated in defence. For Man City, they lost Aymeric Laporte, Benjamin Mendy, John Stones and Oleksandr Zinchenko for numerous games throughout the season. This spread the injuries between centre-backs and full-backs. For Liverpool, however, all of their serious defensive injuries were suffered by their three main centre-backs – Virgil van Dijk, Joe Gomez and Joel Matip.
Additionally, each team suffered a serious injury to one of their forwards (Leroy Sane for Man City and Diogo Jota for Liverpool). Yet while Manchester City escaped relatively unscathed in midfield, Liverpool has not been as lucky. Three of Klopp’s midfielders have missed 40+% of the season to injury. This is reaffirmed when breaking down the injury scores for both teams by position – goalkeeper, defence, midfield and attack.
Liverpool has a higher average score than Man City for three of the four positions except amongst the forwards. Though it is important to note that the injury score for the forwards is inflated by one serious injury each (Sane for Man City and Jota for Liverpool). If you remove both of these injuries then the average scores are roughly the same at 0.064 for City and 0.036 for Liverpool. It shows that, bar these two injuries, the forwards for both teams have stayed basically injury-free throughout their respective seasons.
WHAT DID THESE INJURIES MEAN FOR THEIR RESPECTIVE STARTING XI’s?
Given that both teams suffered their highest concentration of injuries in defence, let’s evaluate the impact of these injuries on the defensive make-up of both teams. Below is a table comparing the respective starting defences for Man City and Liverpool for each Premier League game:
The thick horizontal black lines connote the loss of a defensive player to serious injury, one that left them sidelined (or will) for at least ten successive games. Man City lost Laporte in Matchday 4, meanwhile, Liverpool lost van Dijk during Matchday 5, Gomez before Matchday 9, and Matip during Matchday 21.
What is most striking is that Pep Guardiola drafted in defensive midfielder Fernandinho to plug the hole in defence. The Brazilian would go on to start 20 successive games at centre-back, providing a stable figure in City’s backline while Laporte recovered from his knee injury. Though his partner would vary between Nicolas Otamendi, John Stones, Eric Garcia and fellow midfielder Rodri, having a consistent figure at centre-back undoubtedly helped City to steady the ship and come out of the situation relatively unscathed.
On Merseyside, Jurgen Klopp was not able to find a player who could offer the same kind of stability that their rivals had. Liverpool have had 16 different centre-back partnerships in the league so far this season, compared to City’s eight (excluding the two games with three centre-backs). Most notably though, they haven’t had one central figure throughout, a far cry from last year where van Dijk played every single minute of every Premier League game. Gomez, Fabinho and Henderson took it in turns to share the burden, but each suffered injuries that prevented them from providing the same kind of stability as City had with Fernandinho. That does not mean Liverpool has not had a consistent figure in their defence. Andy Robertson has only missed five minutes so far. Yet, as a full-back, he does not have as big an influence on the defensive organisation of the back-line as one of the centre-backs.
The ramifications of this for the rest of the team have been well-documented. In my previous pieces I highlight the “domino effect” these injuries have had on the other positions. While Man City were able to contain their issues to their defence thanks to their outstanding depth, Liverpool did not have the same luxury. The season-ending injuries to their three main centre-backs left them drafting in youngsters Rhys Williams and Nat Phillips, as well as recruiting stop-gaps in Ozan Kabak and Ben Davies during the January transfer window. Yet they were often paired with either Fabinho or Henderson, taking away their midfield output. As a team, Liverpool has struggled to fill their voids in the middle, with Klopp now realising that it is better to play his midfielders in their preferred positions and allow what defenders he does have to form a partnership together for the remaining ten games of the Premier League season.
There is a lot to be learnt from what happened to Liverpool this year. From rotation to having adequate cover at every position, the way a club deals with the unfortunate reality of injuries has probably never garnered as much coverage. It is something that affects every team, but not all teams equally. Understanding that distinction is important when discussing who has had it “worse”.
Football Annalytics 