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.