What does the data tell us about this season’s unpredictable Serie A title race?

It has been a long time since the Serie A was so competitive and tense. Juventus have won the title for nine seasons in a row and most of those times, they won it by a large margin. Napoli, Roma and Inter were the teams that have come close to dethroning Juventus in the last nine seasons, however they all ended up short on that account. This season, however, reminds us of the period at the beginning of this century when there were quite a few teams that could win the title. Some of the top teams are looking to exploit Juventus unexpectedly bad campaign thus far and push for the title. We are witnessing an AC Milan renaissance with the veteran Zlatan Ibrahimović as the key figure of their successful season so far, while the likes of Roma and Inter Milan also have credible shouts to be in the title race.

Through this data analysis we will take a look at the numbers of the Serie A clubs so far and compare them across different statistics. This analysis will show us which teams could have an advantage over their table rivals based on the data. From the top seven teams only Inter will not participate in the knockout phase of European competitions which could be an advantage for them in this seasons tight schedule. 

Performance and expected goals model

The first graph we will analyze consists of created metrics called defensive and offensive performance. Both metrics are in percentage value and they represent the team variance between xG and goals. 

There are four teams that are overperforming for both expected goal values on this graph: Sassuolo, Napoli, Juventus and Inter. We can see that Sassuolo are overperforming defensively by around 40% with only Milan and Hellas Verona in front of them. However, both Milan and Hellas Verona are underperforming offensively while Sassuolo are the biggest offensive overperformer with around 20% better outcomes than expected. Juventus, Napoli and Inter are close on the graph, and also on the league table. It is a little worrying for Juventus that they are overperforming in both metrics but they sit in 4th place meaning they haven’t played at the level everyone expects them to be at. Hellas Verona are the biggest defensive overperformer and big praise goes to Marco Silvestri for this. Silvestri has managed to keep 5 clean sheets and concede 18 goals in 19 matches making Verona the team that has conceded the least number of goals in the league. Udinese have not shown too many poor performances this season, however they are the biggest underperformers and could probably be in the top half of the table if they had a better conversion rate. Fiorentina are a team that has made a negative surprise on this graph given the number of well-known players they have in their squad. 

The next graph will show us xG values to see the quality of the team based on the quality of chances created and allowed.