Last Updated: 17-02-2020
The UEFA Champions League has always held a very fond place in my heart.
Growing up in the UK, this along with the FA Cup was the only live football
you could watch on terrestrial television all year round. The dramatic theme tune,
the star-mosaic ball logo and even the mastercard adverts
still invoke a deeply rooted sense of nostalgia that is difficult to contaminate.
However, the most alluring aspect was watching mysterious giants from the continent collide. In a pre-internet
age, and without the omnipresent coverage of European domestic football on television or online, you
watched the game through an unbiased lense and enjoyed the spectacle for what it was, 90 minutes
of (usually) high quality football. It would otherwise be an opportunity to watch footballers in other leagues with huge reputations that you would hear so much about, and to evaluate whether the hype was warranted. For my generation this was footballers like Zidane, Del Piero or Ballack. Growing up as a Tottenham Hotspur fan I yearned to watch us
compete against European juggernauts, and until I was 17, I would have to settle, in envy, for watching our rivals
playing in the pinnacle of club football.
Growing up, devouring copious hours of football by absorbing as much football
on television as possible, or through playing games like FIFA and Football Manager, or
following other football fanatics on twitter, the mysterious veil of watching footballers I had no idea about has dissipated,
but my love for the Champions League has not.
As the knockout phase begins this week, let's look at some stand out performers from statistical perspective in the
group stage, and identify players to look out for going forward this season.
The theme of this season's Champions League has been youth: particularly at the offensive end, spectators have been treated to what the competition might look like in a post Ronaldo & Messi era. Erling Braut Håland, Ansu Fati and Rodrygo all announced themselves on the international stage in the group phase this season. With Håland's transfer to Dortmund, we will still enjoy their exploits in the coming months.
5 - Red Bull Salzburg’s Erling Haaland has become the first teenager in the history of the European Cup/UEFA Champions League to score in five consecutive appearances in the competition. Famous. #UCL pic.twitter.com/6YYNOVXFgb
— OptaJoe (@OptaJoe) November 27, 2019
17y 40d - Ansu Fati has become the youngest goalscorer in Champions League history, scoring for Barcelona tonight aged just 17 years and 40 days. Whippersnapper. #UCL #INTBAR pic.twitter.com/z8TRAsr9Z9
— OptaJoe (@OptaJoe) December 10, 2019
18y 301d - Rodrygo has become the second youngest player to score a #UCL hat-trick, after Raul against Ferencvarosi in October 1995 (18y 113d). Hero.
— OptaJoe (@OptaJoe) November 6, 2019
My usual habits after each Champions League match day is to look through the teams that played and their line ups, and browse the individuals that featued. Something that struck me this season during this neurotic practice, was the number of young players populating the line ups of teams such as RB Salzburg, RB Leipzig or Genk.
Below is a chart of the average age of each squad weighted towards minutes played. Due to UEFA Squad registration rules, each team will have a number of young players feature in the squad, but I’m more interested in teams that give substantial minutes to these youngsters.
As we can see, Genk have an average team age of 23 years old. They have a squad littered with some emerging young talents such as Sander Berge, who’s performances have earned a Premier League transfer to Sheffield United.
A downfall of evaluating a teams youthfullness in this way is that often, an experienced goalkeeper or left back may drag your average age up, or one exceptionally young talent may drag it down. A better way to evaluate might be to look at the number of players below an age we deem as 'young'.
Below is a scatter chart of players of 23 years or younger, by age against minutes played. For the same reasons as for the chart above, I’ve only included players that have completed 45 minutes or more during the group stage. This gives us a chance to look at players that have featured as integral squad members at some point or another, and excluding players that were selected to comply with competition rules, or those given very sparing or inconsequential cameos.
By selecting a team in the drop down above, you can filter the chart to look for players from that team specifically, ‘All Teams’ will reset the chart to include all teams.
Most notable from this chart is Rasenballsport Leipzig, who have 13 players 23 years or younger that have played 45 minutes or more. This exemplifies their focus on scouting young talent that has been a hallmark of the Red Bull groups modus operandi for the last decade, which is now coming into fruition.
While we may not see Salzburg or Genk in the knockout phase, it will be intriguing to see which young players make a name for themselves at Leipzig, and possibly earn a big summer transfer to an elite club.
As mentioned above, Håland earned himself a move to Borussia Dortmund. Judging from his goalscoring record so far in the bundesliga, we will hopefully see him score as clinically as he did in the group stages:
A question we may ask about the featured young players in the group stage is where they hail from. The chart below shows the nationality of these players. France boasts nearly twice as many young players (with substantial minutes) as the next best country: Brazil. Unsurprisingly France, England, Spain, and Germany feature highly on this list, and regularly perform well at youth tournaments, such as the Spain side that won the U21 European Championship just before this season's Champions League season started.
Notable on this list are Nigeria, Norway and Cameroon - these are sides that do not have any sides competing in the competition nor are placed in the top 20 of FIFA’s international ranking. This indicates a bright future for these countries. For me personally I’m intrigued to see how Norway develops in the coming years with prodigal youth players such as Håland, Berge and Odegaard.
In recent years, xG, or expected goals has seen a rise in popularity. A breakthrough moment in the UK was when Match of the Day included it in their statistical description for games. In other media sources it has taken more time to permeate into everyday discussion of football.
For the uninitiated, xG is a stat that quantitatively describes the quality of a scoring opportunity. To determine the quality of an opportunity, the chance is compared to other shots with similar parameters, such as area on the pitch; whether it was a volley or header; if the player was using their left or right, and if that’s their strong or weak foot. The fraction of these comparable chances converted from the total is the xG value. If 1 in 10 shots from 25 yards out, from a right foot volley are scored, then the value is 0.1. The higher the value, the easier the chance - an open goal from 1 yard out is virtually 1, but a weak foot shot from near the sideline would have closer to 0. We can summate the value of these chances to describe the quality of chances a team had during a game - which is why each chance is measured as a decimal, rather than a percentage.
For me personally, it is just the next evolution in describing a match that is not very well represented by it’s scoreline. We’ve all seen a match where our team has lost 1-0 but squandered a glut of chances. Previously we would just quote how many shots our team had in comparison. A few years later we would describe how many shots on target to emphasise the quality of those chances, sometimes we may even quote how much more possession we had than the other team. Expected goals just gives us an idea of the grand sum of chances both teams had, and can be used to highlight when a team has undeservedly (unless it’s your team) won a match with inferior chances.
The chart below shows the sum of actual goals minus the xG sum by club - this highlights teams that have, either clinically and/or serendipitously converted unexpected chances. As expected, xG to Goal deficit doesn’t match up with team performances in the group stage. As many teams qualified with a positive deficit as those without.
This can be explained with two schools of thought: teams that are clinical make the most of their chances to win games, and good teams don’t need to be as clinical when they have the creativity to carve out a copious number of opportunities to score.
A notable team in this chart is Atalanta. After 3 games they sat firmly at the bottom of group C with 0 points, but the general consensus was that their performances weren’t being rewarded with proportional results. The chart above illustrates how unlucky teams can be. Fortunately for Atalanta, their potency was much higher in their final 3 games, but the frequency in creating chances was the same.
Another stand out team from the chart above is Bayern Munich. As I mentioned above, being a Tottenham Hotspur fan, I have a fairly vivid idea of how ruthless Bayern can be:
These goals illustrate what converting a low xG chance looks like. Many of these goals are hit outside the 18 yard box - let alone the penalty area. It’s no surprise that if we took the chart above and broke it down by players and looked at the top 20, that Robert Lewandowski and Serge Gnabry lead the charts, illustrated in the chart below. In the video featured above, all of their goals land within a yard of the post, if not hitting the post on the way in. While the Spurs midfield and defence could have done better to prevent the chances from being created, Hugo Lloris simply found himself in the wrong place at the wrong time.
If we look at the opposite end of the scale we see the players that squandered the best or many chances. Marco Reus leads the competition as the most wasteful player and it’s interesting to see if Erling Braut Haland can be more ruthless in the second half of the competition for Dortmund. In second is Tammy Abraham, which gives credibility to the rumors that Chelsea had been looking at possible transfers upfront in January after having their transfer ban lifted.
A player to look out for in the second half of the competition may be Alex Oxlade-Chaimberlain. He impressively scored 3 goals, despite having a sum of 0.5 xG. While this goal against Manchester City was scored nearly 2 years ago, it serves as a good example of how capable he is if his injuries are fully behind him.
The UEFA Champions League has historically been a pantheon for mercurial playmakers, like Zenidine Zidane, Gheorgi Hagi and Xavi Hernandez. Last season Ajax’s Hakim Ziyech was a revelation, along with Frenkie de Jong and Dusan Tadic, Ziyech impressed audiences through the semi finals, and it looks his form carried into 2019/202, while Ajax may have not. Zyiech's performances in 2019 were enough to persuade Chelsea to part with the best part of a reported £34 million fee for his services next summer.
7 – Ajax’s Hakim Ziyech has now either scored or assisted in each of his last seven Champions League games away from home (3 goals, 5 assists). Globetrotter. #UCL pic.twitter.com/xj1qJyLOek
— OptaJoe (@OptaJoe) November 27, 2019
Similarly to xG, expected assists, or xA, can show us players that serve up great chances for team mates. This season Hakim Zyiech features 4th in disparity of xA and Assists. Ahead of him and everyone else in this regard is Corentin Tolisso, who, unsurprisingly featured in the infamous match against Spurs.
At the other end of the scale it’s not surprising to see Thorgan Hazard feature highly. Marco Reus, and Dortmund as a whole squandered a lot of chances, but serendipitously edged past Inter Milan to join Barcelona at the top of group F. What is a little more surprising is to see players like Veratti (PSG) or Alaba, Thiago & Kimmich (Bayern) who featured for sides that were above their goals scored in xG chances created.
With the high calibre of players that feature in the Champions League, fans are frequently treated to mesmerising dribbles. If this is what you look for in games, the teams below might be the teams to look out for in the coming months of the competition.
If we want to turn our focus to individuals rather than teams in general, here are the top 40 players in the competition so far.
This is the top 40 players in terms of dribbles attempted per 90 minutes. Despite waning in age, Lionel Messi leads the charts in attempts per 90. Despite missing 4 and a half games, Neymar wasted no time in his short lived cameos to trail second behind Messi.
In the coming months, and as PSG look to Neymar to lead them to glory this season, he will be taking the ball and running at opponents. However, this chart only describes attempts - who has completed the most dribbles?
Looking at completed dribbles per 90 minutes, Lionel Messi’s lead over the rest of the competition extends.
What is impressive about this, is not just the volume of attempts he is making, but how many are successful.
Lionel Messi burst onto the scene nearly 15 years ago with his penchant for dribbling past defenders, and it’s nice to see all those years later, and adapting his game multiple times, that it’s still a big part of his game.
Even as he approaches his mid 30s, and as he physically degrades, he is still the most difficult player to disposes when he runs with the ball.
A few other stand outs here are Ndombele, Emre Mor, and Vitolo who don’t feature highly in attempts, but jump up the rankings in completion.
Unfortunately, only the first of these 3 will feature in the coming month(s).
Denormalising the numbers, and looking only at the total number of dribbles, its not surprising to see Lionel Messi so
far ahead of the rest of the pack.
While the next 3 players on the list were with teams that didn't qualify for the next stage, it will be exciting to watch on as Jadon Sancho, Houssem Aouar and Eden Hazard attempt to drift past defenders with the ball at their feet.
Whoever features in the coming months, hopefully we will be treated to more like this:
Having previously looked at the players most relevant at the offensive end, it would be shortsighted not to look at those most impressive defensively this season.
A single stat appreciated by most purists is interceptions - which can be encapsulated by this quote by Maldini:
Paolo Maldini: "If I have to make a tackle then I have already made a mistake."#WednesdayWisdom #UCL pic.twitter.com/ztXs6CxFlf
— UEFA Champions League (@ChampionsLeague) November 8, 2017
By looking solely at defenders, we see just how much Mats Hummels stands out - especially as the other Dortmund defenders rank fairly lowly in this regard. As he’s aged, his ability to read the play has improved, and to cut out attacks before more physical action is required.
Among midfielders, Walter Barrios stands out as having many interceptions - on average he completes around 4 interceptions per 90 minutes, and completed 5 more interceptions than any other player.
Aside from interceptions we can also look at the number tackles - particularly for players that may be left exposed by team mates or systems that mean they are regularly left isolated against the dribblers mentioned in the chapter above.
Ismaily of Shaktar Donetsk led the competition in tackles, but also accumulated a substantional number of minutes.
If we normalise by minutes played, and also compare to the number of duels lost, we get a better idea of who performed impressively in this regard.
Players in the top left are those that frequently tackle their opponents, and are infrequently (if ever), find themselves watching players race away after attempting to tackle them.
Players in the bottom right are those that rarely complete tackles, and often find themselves watching players galloping away.
Among defenders, Merih Demiral stands out, despite having limited duels, has 100% tackling success. Among defenders with a high volume of duels, Panagiotis Retsos stands out in generally getting the better of his opponent.
If we look at midfielders - for whatever reason, fbref.com, the website I have sourced the data has listed Jean-Clair Todibo as a midfielder, when others have listed him as a defender. Regardless, he stands out among all players.
However, this is caveated by the fact he only played 1 game (very competently) in the group stage against Inter Milan.
Among actual midfielders, Leandro Paredes stands out in having getting the better of his opponent while having a high volume of duels. For me, Florentio Luis also stands out - he may be dribbled past as many times as he completed tackles - but the number of duels he is involved in per game, 10, is among the highest in the competition.
Ideally, you would have your players complete all of their tackles, but for a young player, it requires anticipation to be in the right place to contest these challenges. As Florentino Luis grows, and gets stronger, his completion will rise.
Now that we are in February and the opening games of the knockout phase of the UEFA Champions league starts this week, I hope this article has given you enough to whet your appetite for the upcoming fixtures. Personally, I will be following Håland at Dortmund with great curiosity - his opening 305 minutes at Dortmund have yielded 8 goals, and he looks set to add to the 8 he scored in the champions league so far this season.
Among other players, I will be intrigued to see how the youthful Leipzig fair against my beloved Tottenham Hotspur. I’ll also be looking out for Florentino Luis to understand how he finds himself engaged in so many duels in the middle of the park.
Some of the more impactful young players of the latter stage of the competition might even be players that didn’t feature in the group stage. 22 year old Steven Bergwijn joined Tottenham in the January transfer window, and if his debut goal against Manchester City is anything to go by, he may well have an impact in the coming fixtures against Leipzig.
All of the data for this article was sourced from fbref.com.
The code to generate this page can be found on my github repository.
If you enjoyed this article, or have other questions, get in touch by email, through my twitter, or through LinkedIn.
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