Behind Enemy Lines: Liverpool FC

Narratives vs Randomness

We love to think that the world is deterministic. Our brains are hardwired to find cause-and-effect relationships. We want to think there’s a story behind every phenomenon. Our minds find solace and certainty in these explanations because if there’s a deterministic cause, then we can control that cause and control our destiny. We want to believe that all success in life—including that of our football teams—can be controlled, and that passion, drive, intelligence, and hard work will always lead to success.

But that’s not how the world works. More often than we’d like to admit, our successes and failures come down to random factors outside our control. And that lack of control scares us. That fear is why so many people are attracted to conspiracy theories, for example.

I say all this because sports commentary is no different, and I never cease to be amused by our stubborn attempts to find narratives that explain the results of our football teams.

xkcd https://xkcd.com/904/

The football discourse has tried to come up with a myriad of explanations for why Liverpool are not doing well this season: maybe Klopp’s cycle is over, maybe they got complacent, maybe they lack the “winning mentality“ of previous years, maybe they lack a leader without Van Dijk, maybe the signing of Thiago was a bad idea. However, Liverpool’s fall from grace this season has more to do with unlucky streaks and injuries that were outside of the control of Klopp and his team.

In previous years, Liverpool had been both really good AND really efficient in the boxes, to the point they were much better than their underlying expected goal (xG) numbers. It’s amazing that they kept up this momentum and confidence for two years, as it’s almost impossible to maintain such efficiency for such a long time. This season, Liverpool’s xG numbers are slightly worse than last season, but the biggest difference lies in their efficiency and execution. Last season they were ahead of their xG difference by a stunning 20 goals, this year they lag behind xG difference by 3 goals.

To make matters worse, Liverpool suffered the season-ending injuries of three center backs—Van Dijk, Joe Gomez, Joel Matip—and now even key midfielder (and emergency defender) Jordan Henderson also seems to be out for the rest of the season. These absences, especially that of Van Dijk, have had major knock-on effects on the team’s structure and systems.

The Knock-On Effects of Center Back Absences

Without the center backs, the most defensive central midfielders in the side—Fabinho and Henderson—were forced to put in a shift in the defensive line, leaving “softer“ midfielders like Thiago and Curtis Jones in charge of defending the midfield zone. This restructuring not only affected the defensive cover available to Liverpool fullbacks but also their offensive impact.

The case of Trent Alexander-Arnold is paradigmatic. Van Dijk provided diagonal long balls from the left that allowed Trent to receive the ball further upfield, while Henderson on the right provided good movements and runs to support Trent. Henderson also provided defensive cover for Trent, who is a world-class creative fullback but has some defensive weaknesses.

Without Van Dijk and with Henderson’s move to the defensive line, Trent lost a lot of this defense and offensive support. As shown by the chart below from Josh Williams, Trent is struggling to receive the ball upfield and is forced to do more ball progression work from deep areas instead of creating shots for his teammates. The changes of this season have reduced Trent’s impact in the final third while also making him more vulnerable in defense. The worst of both worlds.

The absence of Van Dijk and the shift of Henderson and Fabinho to the defensive line also makes it harder for Liverpool to keep a high defensive line and a super-compact pressing shape. This has created more gaps in between their lines that can be exploited by opponents and has made their high line particularly vulnerable to through balls. As shown by the John Muller plot below, Liverpool are now the worst team among the big 5 leagues at conceding through balls.

John Muller https://spacespacespaceletter.com/throughballs/

The Impact of Thiago

The ever-ambitious Jürgen Klopp knows better than anyone that even if his team was at the peak of their powers in 2020, he needed to rethink his approach to keep winning. Liverpool’s days of supreme efficiency in the boxes would soon come to an end, his forward trio is dangerously close to 30, Henderson is aging too, Wijnaldum is leaving, and young talents like Curtis Jones and Harvey Elliott are more passers than runners. Liverpool’s offensive system—based on long passes that bypassed midfield and went straight to the forwards— had to be updated.

This rebuild motivated the Thiago transfer. While the classic Klopp Liverpool midfield controlled games by what they did without the ball, it seems that Klopp now wants to build his next great Liverpool side by having a new midfield that can control and create more with the ball.

The passing networks below exemplify what I’m talking about. The network on the left is from Liverpool’s latest game this season against Manchester United (01/17/21), with Thiago starting. The network on the right is from a game against United from the previous season (01/19/20). Notice how the passing network from this season has more connections through Thiago in midfield areas than the one from the previous season, which has mostly connections on the wings. Instead of playing through the fullbacks or pinging long passes directly to Mané and Salah, Liverpool are now playing through Thiago, who is looking for shorter passes through the center.

Between The Posts https://betweentheposts.net/match-plots/

This change of style, while likely needed in the long-term, is not a great fit right now for Liverpool’s forwards. Liverpool having longer possessions and shorter passes leads to Mané and Salah having less space to run in behind defenders or take them on. Thiago also struggles a bit with the defensive tasks expected of a Klopp midfielder, and that is reflected in the fact that he’s the Liverpool player who commits most fouls per game.

Jota Refreshing the Forward Line

It hasn’t been the best season for Liverpool’s traditional forward line. Salah is still among the top scorers in the league, but his non-penalty expected goals (npxG) has dropped by a full 28% compared to last year. He is getting into shooting positions less frequently and his dribbling success rate has also dropped. Meanwhile, Mané’s underlying npxG remains stable—he’s shooting even more frequently than before—but he has been let down by his finishing. Mané is scoring at half the rate of last year and lagging 5 goals behind his xG.

In previous seasons, Liverpool could simply send long passes or crosses to Mané and Salah and rely on their individual quality and efficiency to get the job done against the opponent. This year it has been more difficult for them to beat and outsmart opponents, and that has led to several games in which Liverpool fail to score despite setting up camp in the opponent’s box.

Photo by Emilio Andreoli/Getty Images

Fortunately for them, reinforcements arrived this season in the form Diogo Jota, who can claim to be Liverpool’s most in-form forward this season. The Portuguese is an extremely versatile and complete attacker: good dribbler, great pressing workrate, good longer movements behind defenses as well as smart shorter movements inside the box, and can even play as a striker if needed. And this season, his finishing is on fire: he is doubling his xG and has scored one more goal than Mané in the league with just a third of the minutes.

To add to Liverpool’s injury woes, Jota suffered a knee injury that left him out of action for three months, between December and February. Perhaps Liverpool would still be in the title race had he been fit. Jota might not start against Real Madrid but he can still be decisive as an impact substitute: his two goals against Arsenal this past weekend are a good example of what he can do against tired legs when coming from the bench.

To Back Three or Not to Back Three

Ahead of this game, Zidane still has to cope with the major absences of Dani Carvajal and captain Sergio Ramos. Eden Hazard has started training with the squad again but he didn’t make the squad list for this game, so Zidane and his staff still don’t see him as fit enough to play a game of this caliber.

The big lineup choice question for the evening is whether Zidane will continue using the back three setup even in the absence of Ramos. The weekend game against Eibar hints that Zidane could continue using it, with Varane-Nacho-Mendy as the three center backs. However, this would require Marcelo to start and there are legitimate concerns about his ability to handle the speed of play of Liverpool. If Zidane chooses a 3-5-2, the other lineup question is whether Benzema’s partner in the attack will be Vinicius—arguably the best fit to attack Liverpool’s high line—or an Asensio who had a positive performance against Eibar.

If Zidane chooses a back four, he might not also not go for the typical 4-3-3. He could choose a fourth midfield to start alongside Casemiro-Kroos-Modrić: Isco could be useful to handle Liverpool’s pressing, while Valverde could be a better match in terms of physical intensity.

All in all, even though we know what 9 out of 11 names in the lineup will be, the shape and game plan of the team remain a huge question mark that only Zidane knows the answer to.

Liverpool Lineup Choices: Wijnaldum or Jota?

I spent 1300 words telling you that Liverpool are worse now than they were last season, but we should consider that they have finally found some stability over the last month with the center-back partnership of Nathaniel Philips and Ozan Kabak. Injuries have ravaged Liverpool’s defense so much that these two are the center back pair with most minutes this season even though they have only played four games together.

Those four games have led to four clean sheets, not just because of the defender pair, but also because this has allowed Fabinho to return to his holding midfield position and provide more balance in the midfield areas.

So even if they don’t have much experience in these kinds of ties, it’s very likely that Philips and Kabak will start against Real Madrid too. The mainn lineup choice for Liverpool is who will start alongside Thiago and Fabinho in midfield. The most likely option is Klopp’s trusted lieutenant Gini Wijnaldum, which would make Liverpool retain their usual 4-3-3 shape.

If Klopp is feeling adventurous, he could go for the same lineup he used in the second half against Arsenal: a 4-2-3-1 with a Fabinho-Thiago double pivot and a front four of Salah, Mané, Firmino, and Jota. Klopp will likely be conservative and not start with this plan, but it could be a very dangerous plan B for the second half.

Key Matchups

Photo by David S. Bustamante/Soccrates/Getty Images

On the defensive end of the pitch for Real Madrid, the most impactful matchup will be Ferland Mendy against Mo Salah. Even with a decline in some of his numbers, Salah is still the most impactful attacker for Liverpool: not only does he get in the box and score, but his combination play with Alexander-Arnold also helps create chances. This time, however, he will face one of the best 1v1 defenders in the world, and if Mendy can win the duels against him, Liverpool’s attacking threat would decrease considerably.

Photo by Diego Souto/Quality Sport Images/Getty Images

On the other end of the pitch, watch out for Benzema against Kabak and Philips. If you’re a center back who lacks elite positional awareness and experience in elite knockout games, Benzema is one of the worst possible matchups for you. Benzema is an intellectual rather than physical challenge for defenders: his movement could drag Kabak and Philips out of position and generate gaps in Liverpool’s defensive line that could be exploited by his attacking partner—Asensio or Vinicius.

Photo by Diego Souto/Quality Sport Images/Getty Images

Finally, watch out for the battle of Kroos and Modric against Liverpool’s pressing system. Despite the high-line struggles, Liverpool are still one of the most aggressive and effective pressing systems in Europe. The main defensive objective of Liverpool’s midfield and forwards will be to prevent the ball from reaching Kroos and Modrić. Liverpool’s pressing structure is a big reason why Zidane could deploy a back three: matching Liverpool’s forward trio with three center backs might make it easier to reach the central midfield duo.

---