The good folks here at StatsBomb are very excited about the Champions League final. We’re so excited that we wanted to make sure we got some of our cool new toys out in public view before the last match of the season kicks off. This involved making a compromise or two. The data isn’t quite done yet. Such is life in big data city. Who knew launching a technology company could be so hard? But, rather than deprive the people of what they want (and we are quite confident that what the people want is pictures with bright colors and lots of squiggly lines), we just decided to make do with some slightly incomplete data. Here, without further ado, are a bunch of cool pictures that help explain why Liverpool are so dang good. They just happened to be drawn from a slightly incomplete picture of 32 matches of Premier League data rather than waiting for our diligent data mice to finishing sewing the last six games in.
Liverpool’s Defensive Pressure.
We’ve talked about a lot about how we record pressure in matches. Liverpool are a perfect example of how doing that helps paint a fuller data picture of what a team is actually doing on the pitch. Here’s what Liverpool look like as a defensive team without pressures included. It paints a pretty good picture. The degree to which Liverpool bother opponents deep in their own territory is apparent. Looking at that map it doesn’t get anything noticeably wrong. Now, let’s look at a map with pressures included. Yowser. This really makes clear how aggressively Liverpool are taking the game to opponents. Those on ball actions don’t come from nowhere. Liverpool contest everything across the field, and it’s those actions that force opponents back and into the kinds of mistakes that ultimately lead to turnovers and easy opportunities for Jurgen Klopp’s band of merry pressers to take advantage of. Now, let’s look at the same dynamic on an individual player level. Here’s Roberto Firmino’s defensive actions without pressures included. Firmino has rightfully garnered a reputation as a player willing to do tremendous amounts of defensive work for Klopp’s side, exactly the kind of high motor ball harassing forward a good pressing team needs. This particular chunk of data doesn’t disprove that, but it doesn’t exactly prove it either. It shows a player who is quite active in a fairly limited forward zone. Clearly he’s committed defensively, but the breadth of his commitment is still mostly something that data didn’t capture. And now to add in the pressure. Hey there Bobby! That’s a more accurate picture of the player we keep seeing on the pitch. Add in pressure events and Firmino’s defensive range and determination becomes much more apparent. All this pressing information is contained on Liverpool’s defensive radar too. The radar in particular shows Liverpool with a very high defensive pressure rating while only having a mediocre pass per defensive action score. That, in part, is because of the presence of all those pressures. Liverpool have a cohesive pressing unit that makes life difficult for opponents even when they aren’t tackling, intercepting or otherwise actively taking the ball away. The one possible fly in the ointment here is that Liverpool’s xG per shot conceded is below average. It’s tempting to look at that is a result of the tradeoffs a pressing team makes, a concession that when the press is broken opponents will get very good shots. It turns out that’s not the case for Liverpool, at least not this season. The result of all of Liverpool’s effective pressure is that the team simply doesn’t give up a lot of shots of any variety. They restrict opponents bad shots, and they also don’t concede very many golden chances either. Opponents simply have a very hard time creating anything against this Liverpool defense. Teams' average xG per shot isn't higher against Liverpool because they creati more good chances. They don't. Rather, it's because in addition to preventing good chances Liverpool also prevent a high number of bad ones. Salah Days It will not surprise anybody with a pulse that Mohamed Salah is the central hub of Liverpool’s attack. The attack does almost everything well. They keep possession and pass the ball from back to front and take an avalanche of chances. The only place where they might get a slight demerit is the average shot quality of their chances, but that's largely a function of how often defenses sit deep and make themselves difficult to break down. Sometimes there’s not much to do but hammer away with mediocre chances until one finally goes in. The majority of the goal scoring thrust obviously comes from the front three of Salah, Firmino and Sadio Mane. And, of course, Salah in particular has had an absolutely unstoppable season. His scoring numbers crashing into the box from his right side wide forward position are enormous. It’s not just that he’s cutting off the right side and onto his stronger left foot to terrorize the defense, it’s that when he does that he consistently gets deep into the heart of the backline trying to stop him. Ineffective wide forwards end up cutting in and shooting from the edge of the 18. Salah, on the other hand, lives six to twelve yards out. Oh, in case you’re wondering why that one Salah goal he scored from the parking lot seems like a good chance. It’s because it actually looked like this. Despite Salah’s magnificent scoring season, Liverpool’s attack remains highly balanced. Looking at the distribution of the team's xGChain per 90 (among players with more than 900 minutes played because I'm mean and wanted to deny the departed Coutinho any glory) paints a picture of a team operating with Salah as the first among equals rather than a lone superstar. He might get to finish a disproportionate number of the moves, but Salah is standing on the shoulders of all of his teammates working to find good opportunities. So, that’s Liverpool. They’re a hard pressing, high scoring, beast of a unit. Now, we have more ways than ever to show how they do it. Images provided by the Press Association