In this blog I am going to have a deep dive into Bayern Munich’s Polish striker Robert Lewandowski. Lewandowski is of course a huge name in football, with a great goalscoring record, at club level and international level. Lewandowski recently signed a new 4 year deal with Bayern. Is this a good deal for Bayern, tying down one of the top strikers in Europe, or have they tied themselves down with a striker who is past his peak?
Now, simple stats like goals scored can tell some stories, but I need to go deeper to find out the true story. I am going to look at expected goals, which has come into the forefront of football stats over the past few years, along with a few other stats. I like to use a great site – Understat.com, which is one of the top resource websites on the net for expected goals, and if you are a fan of stats in football you should check them out. I have collated a lot of information from there, and added in some calculations myself to try to get a true picture of Lewandowski’s recent form.
In this blog, I will be talking expected goals, goals per 90 minutes, and shots per 90 minutes over the past 5 seasons.
I decided to look further into Lewandowski when I started looking at strikers who had scored 10 or more goals this season in the top 5 leagues in Europe (Germany, England, Italy, France and Spain). What stood out to me was the difference between Lewandowski’s goals scored to his expected goals.
In theory, these two stats should be very similar, but for a top level striker their actual goals scored should be higher than their expected goals. Basically, that shows that they score tougher chances. Someone who has a higher expected goals total than goals scored, shows that they are missing chances than they should be expected to score. What I’m also using is non penalty goals, which means that any penalties are not taken into account, so it is all based on open play goals.
To give an example, and this won’t be a shock to anyone, Lionel Messi had an xNPG (Exepected Non Penalty Goals) total of 22.28 goals this season, but actually scored 32 non penalty goals. That is the sign of a top level striker. On the other side of the spectrum, was Lewandowski. He has an xNPG of 33.14 goals, but only scored 22 goals for a difference of-11.14. This was more than double the next worst, which was Andrej Kramaric of Hoffenheim, who had a difference on -5.03 off an xNPG of 17.03 and goals of 12.
So what has caused this? Is it just a one off blip, or is it a sign of a regression of finishing skill for the big Pole?
First thing I look at was Lewandowski’s shot map for this and something stood out. You will see I have isolated the shots that Lewandowski missed the target with. There are 11 shots that missed inside the 6 yard box this past season. This isn’t shots that have been saved, or hit the post, this is actually missing the target completely. I have also posted shot maps for the previous seasons too and you can see the increase in shots missing the target (he has never missed more than 6 in one season).
The next charts will look at the next two which are xNPG and NPG. Lewandowski’s NPG peaked in 15/16 with 28 goals, but this has slowly decreased to 25, 23 and then 19 last season. In the same time his xNPG has gone from 26.95, to 26.31, to 22.59 but then increased last season to 30.11 goals.
So, maybe the goals scored has decreased due to time spent on the pitch. So I looked at Lewandowski’s NPG per 90 minutes, to see if there is a similar pattern here.
The xNPG 90 has stayed steady over the past few seasons. In 2015/16, it was 0.91, then dropping slightly to 0.85 in 16/17 before climbing to 0.94 in 17/18 and then 0.92 last season.
For the actual NPG 90 this is where it gets worrying. His NPG90 goes from 0.95 in 15/16, to a dip in 16/17 of 0.81 and then climbing back up to 0.96 in 17/18. As you can see, these compare favourably to his xNPG90. There is now a huge drop last season, his xNPG90 is 0.92, but his actual NGP90 is only 0.58.
Now I should say that Robert Lewandowski is one of my favourite players, so I was wanting to find something that would explain this poor season. Perhaps then, he is taking less shots. So I did some analysis on his Shorts Per 90 Minutes.
He has taken less shots than normal last season than the previous few seasons (4.38 per 90 v 5.28, 4.63 and 5.15) but its not enough of a drop to explain the decreases in finishing. In fact, due to the increase in xNPG this season means he is actually getting much better chances this season than in any other season.
Lewandowski turns 31 in the next few months, so it is looking like he has hit his peak at club level and it might be that Bayern need to look for replacement. One player they have been linked with is Timo Werner, so I have looked into Werner to see if he looks like he has what it takes to replace Lewandowski.
Werner started off with low scoring seasons in 14/15 and 15/16 with 3 & 6 NPG respectively. But 16/17 saw big increase with 19 NPGs against an xNPG of only 13.02. 2017/18 saw a slight dip to 11 goals off an xNPG of 12.06 (not a worrying difference as he has scored close to what was expected of him).
This past season saw Werner’s NPGs increase again to 16 off an xNPG of 16.63. It makes you think if Werner had close to the chances that Lewandowski had last season, would this total NPG be in the high 20s?
Werner’s xNPG 90 over the past couple of seasons has stayed even at 0.49, 0.48, 0.43 before jumping up last season to 0.59, while his actual NPG90 has been inconsistent at 0.25, 0.70, 0.40 before jumping up to 0.57. It is interesting that his xNPG90 and actual NPG90 have been very close over the past two seasons.
Werner’s shots per 90 minutes has also increased season on season from 1.67 in 14/15, to 2.62, 2.72, 3.42 and then 3.80 last season.
From the stats available, this could be the perfect summer for Bayern to look at replacing Lewandowski. It does seem strange to say that a striker who only had 5 players score more non penalty goals than him last season in the top leagues in Europe.