Is Trent Alexander-Arnold a defensive liability?
Football is a low-scoring sport with a lot of fast-moving parts. A striker’s (non)action could start a plethora of mistakes that lead to a goal being conceded at the other end of the pitch. The many factors that determine the outcome of a football match make it difficult to objectively evaluate defenders.
Defending, unlike attacking, is about reacting to events on the pitch. This means that almost 100% of the time, defenders are put into defensive situations they did not ask for, which is fair because this is what they signed up for. The main object of defending is to ensure that your opposition’s possession of the ball does not result in a goal against you, and how you go about achieving this depends on the coaches, the players in the defensive situation, or the defensive situation itself.
The consensus in the football community, especially the Premier League, is that Liverpool’s fullback and vice-captain Trent Alexander-Arnold while being an exceptional attacking fullback, is a defensive liability. This has gone beyond just a football narrative, as pundits (who have played the game to a high level) share this sentiment. In fact, the England manager Gareth Southgate seems to make call-up and team selection decisions based on this. The question is: Is the Merseyside boy actually a defensive liability?
Who even is a defensive liability?
To answer, you need to get a clear picture of what it would mean to be a defensive liability. You would also need to get a clear picture of what it means to be a defensive liability in a side like Liverpool, which has constantly returned 90+ league points in the majority of the last five seasons.
If a defensive asset is someone who ensures you always do well defensively, then a defensive liability would be someone who ensures you would always have certain problems in defending. Alexander-Arnold then, by definition, is not a defensive liability. Liverpool’s playing style depends on their fullbacks.
To effectively press your opponents, you need to trap them in the wide areas and then win the ball back there. This means the tackler doesn’t necessarily have to be the one winning the ball back, but he would play a key role.
Jurgen Klopp’s men have been one of the best pressing teams in the country for the past six years, and they couldn’t have done it without getting it right in the fullback department. Alexander-Arnold is not an expert tackler like Leicester City’s Ricardo Pereira or Manchester United’s Aaron Wan-Bissaka.
He is OK, tackling-wise, and that is sufficient for a top level fullback in a top team. This is because tackling is only one aspect of defending out of the many skills you need to be an effective defender. The importance of “reading the game” is so that you can reduce the number of times you need to tackle, as a need to tackle already puts you at a disadvantage.
It would be unproductive to compare the Reds vice-captain with fullbacks of other teams because their numbers are determined — largely — by the system they play in. A better way of evaluating the Liverpool fullback would be to compare him with the other fullback who plays regularly for the Merseyside club: Andrew Robertson, as they both play in the same tactical system.
Let’s take a look at the numbers
According to Sofascore, Robertson unsurprisingly won a higher percentage of his defensive ground duels from the beginning of the 2018–19 season to the end of the 2022–23 season. In that time, the Liverpool left back contested 601 defensive ground duels and won 51.7% of them. Alexander-Arnold won 47.2% of his defensive ground duels, but he contested 47 more ground duels in the time under scrutiny. Considering how regularly they both play, it is telling that the right back has contested so much more than his left side counterpart.
Some fans may interpret this as teams targeting Liverpool’s right hand side, but what is more likely is that teams usually have more threatening players playing as left wingers, and because teams play through their stronger side, it naturally means most teams would trouble their opponent’s right hand side by default. 51.7% to 47.2% is a clear difference, but not a huge difference, especially considering that we’re talking about over 600 ground duels. The percentage difference is not nearly enough to term the latter a liability.
When it comes to actual tackling, Robertson comes out better again, at 66% of his tackles have been successful, compared to 62% of Alexander-Arnold’s, but you’d be right again in assuming that the latter attempts more tackles, because he does. 51 more tackles. For Liverpool’s system, every duel that goes uncontested becomes a serious problem, because of how intricate pressing is.
This is even more true for defensive tackles, as an uncontested dribble means the opponent gets into space to hurt them (at best) or is bearing down on the Liverpool goalkeeper (at worst). This means those 47 ground duels Alexander-Arnold is contesting and sometimes winning makes him crucial to the success of the system.
The numbers have shown that while there is a difference in the tackling abilities of both Liverpool fullbacks, the difference does not justify the criticism the Liverpool vice-captain gets.
Alexander-Arnold defends in other ways
Remember I said tackling is just one aspect of defending? Yeah. Alexander-Arnold has averaged 1.46 interceptions per game in the time under scrutiny. Robertson? 0.78. This suggests the right back has a better reading of the game and better positioning than his colleague. As for clearances, both players are even, with 1.92 clearances per90 for Alexander-Arnold and 1.93 for Robertson.
So is Alexander-Arnold, in fact, a defensive liability? Far from it, the volume of ground duels and tackles he contests makes the case that he’s closer to being a defensive asset for the Merseyside club.
