Liverpool’s Defensive Weakness

When compiling the recent article that I posted where I looked at where teams conceded shots from I came across some interesting findings in relation to Liverpool.

We’ll go for a slight recap and start with the good news for Liverpool; as a defensive unit they were extremely successful at forcing teams to take shots from poor shooting locations:

ShotsConceded

So good were Liverpool in forcing teams to shoot from non optimum positions that they only permitted 18% of shots to come from what I have defined as the Prime location.  As you can see, this value ensured that they led the league quite comfortably in terms of this particular metric.  Of course this fact raises potential questions around how Reina performed in keeping out shots given the great job that his defence did in front of him.  That question can remain unanswered until another day.

I want to look at another feature of Liverpool’s defending that caught my eye; which side of the pitch did the conceded shots originate from.

Background

It surprised me a little to see that 47% of all the shots (excluding headers and penalties) in the Big 5 European leagues last season came from left of centre, 19% were straight on and just 34% came from an area to the right of centre.  I can only presume that the large number of shots from the left side of the pitch is due to the predominate use of the right foot when shooting.  It is obviously much more natural for right footed players to shoot from the left hand side.

From a defence viewpoint the image below shows the areas of the shooting zone that I am defining as right, left and centre of defence:

SidesTemplate

Which side of the pitch did the Premier League teams concede shots from last season?

EPLSidesConcede

Remember, this table is from a defensive viewpoint, and has been sorted in descending order on the Right hand side.

Although there is a heavy bias to all teams conceding shots from their right hand side (this is obviously the other side of the coin to more shots being struck from the attacker’s left side), Liverpool allow a greater proportion of shots to come from their right hand side than any other team in the league.  The league average for conceding shots from the right hand side was 47% but Liverpool allowed in excess of 54% of their shots to be struck from their right hand side.

Their figure conceded down the right of 54.4% is more than 2.5 standard deviations from the league mean which is significant at a level of 1%, or in layman’s terms “there is definitely something happening that causes so many shots to come from Liverpool’s right hand side”.

Is Glen Johnson at fault?

The first possible explanation for this fact that jumped into my head was “Glen Johnson”.  Although Glen Johnson offers Liverpool great attacking potential, in fact he averaged 1.5 shots per game last season which put him just behind David Luiz in terms of attempts by defenders; perhaps these attacking forays come at a price to Liverpool.
I am aware that Johnson didn’t play every game last season and I haven’t yet went to the trouble to separate the shooting statistics for the games that he did play versus the games that he missed.

Whatever the explanation it certainly seems that Liverpool is much more open on their right hand side than any other team in the Premier League.  It’s safe to assume that this fact won’t have gone unnoticed by Premier League managers.

I’m interested to hear any other possible explanations for the heavy bias of shots conceded down Liverpool’s defensive right side.

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10 thoughts on “Liverpool’s Defensive Weakness

  1. Good stuff, Colin. I know from looking at WhoScored that Johnson was dribbled past 29 times whereas Enrique was only beaten 9 times, which may have played a small part in this issue.

    • Thanks Andrew. Decent spot on the number of dribbles that passed Johnson, they would certainly seem to add weight to my possible explanation. I’ve also received feedback on Twitter that Carragher may also have been partly to blame due to the fact that he tended to play as the right centre half.

      Either way, its something that if I was employed by Liverpool FC I would be bringing to their attention.

  2. Interesting, and troubling. The Reina question you hinted at is also worth digging into. Perhaps LFC have realized the answer to that question already re: Mignolet?

    When (if) separating out the Johnson IN matches vs. Johnson OUT matches, keep in mind that he played some matches at left-back as well.

    • Dennis, valid comment re the games that Johnson didn’t play as right back. My data isn’t in the format that allows for easy analysis of the shots conceded that Johnson played, but perhaps its something that I can revisit in the near future.

  3. Johnson has conceded many times rushing back from an attacking position. In fact this has happened when Johnson has played on the left side as well.

  4. why is the central band so ridiculously narrow? most of the interior areas of the left and right sides are more likely the responsibility of the centreback than the fullback….at the least it should be goalpost to touchline..?

    • KIT, you need to think of how this article came about.

      I didn’t start this by doing an article on Glen Johnson’s weaknesses. I was doing some work on shots conceded by each team and in order to aid my analysis I simply split the shots conceded into right and left sides.
      To be honest, if my pitch had an even number of rows I probably wouldn’t even have had a narrow middle band at all.

      So after doing that I seen that Liverpool were the league’s worst in conceding from one particular side – that was the point of this article.
      My hunch that it might be to do with GJ is only a hunch and was put up there as one possible method of explanation. However, the article isn’t about whether GJ is a bad defender.

  5. ….and actually, thinking about it further, the zones of responsibility probably don’t run parallel to the touchline either…..more canted away from the center when moving away from the defended goal, which would probably change the distributions (and their “meaning”) signifigantly

  6. Really interesting analysis. I think you’ve definitely got a point here and Andrew Beasley highlighting the dribbled past deferential between Enrique and Johnson further enforces the weaknesses in Johnson’s game. I do think there are a few points worth considering though. Firstly Wisdom played 12 games on the right hand side last season and I suspect a disproportionate amount of shots came when he played not because of anything he did but simply because I suspect as an inexpereinced teenager he was targeted by opposition managers. I also think both Skrtel and Carragher have a slight tendency to back off a bit and allow low percentage shots from distance. Lastly I don’t think Downing is as good defensively as many suggest, he’s great at getting in position but my observation is he’s a poor tackler and gets beaten too often..

    Last i’m inclined to think this analysis shows that we are quite well organised defensively and perhaps with a more aggressive right sided center back (Toure?) we’ll do better.

    • DanA thanks for your comments.

      As stated above my GJ explanation was just the first thing that popped into my head, and I did say that he didn’t play every game at right back.

      I had hoped to get a more detailed look at how Liverpool performed in games with and without GJ at right back, but just haven’t found the time to do this yet.

      BTW, I hope you have followed me across to http://www.statsbomb.com as that is where I will publish my next articles.

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