On Rafael Benitez in the Premiership and Serie A

It seems fairly likely that Benitez will finally be hired by Madrid in the very near future. I’ve written previously that I think that Liverpool can probably count themselves unfortunate not to win a title whilst Benitez was at the helm, having the misfortune of being a good team at the same time that United were good and Chelsea were tremendous. Below is a plot of the Team Ratings (see here for methodology and validation) during Benitez’s tenure, along with two seasons either side:

Screen Shot 2015-06-01 at 9.56.28 PM

Basically the Team Ratings suggest that LFC were an excellent team in the middle four seasons under Benitez and, despite the fall off in LFCs performance in the final season, Benitez left LFC in decent shape. The decline continued in the season under Hodgson/Dalglish, before their Team Rating picked up in Dalglish’s second season.

I’ve also written about him stopping the bleeding at Chelsea following the train-wreck that was RdM’s tenure. Here’s the plots of Team Rating two seasons either side of Benitez’s tenure at Chelsea:

Screen Shot 2015-06-02 at 9.40.04 AM

Chelsea were in the middle of a pretty serious decline when Benitez took over, and their performance under RdM was really astonishing. That being said Mourinho immediately took CFC back to the Premierships upper echelons in his first season.

As such, I’m fairly solidly in the camp that thinks that in the Premiership Benitez has been a perfectly fine manager at Liverpool and fairly good at Chelsea – had he moved to West Ham I’d have been damn happy. His track record in England is, however, only half of the story – he’s also spent time at Inter and Napoli in Italy.

However I didn’t have an equivalent Team Rating for Serie A, so I built one. I grabbed the data from the last eight seasons in Serie A from football-data.co.uk and built a simple Team Rating based on Goals, Shots on Target, and Total Shots*. The Team Rating is of the equation:

Team Rating = (13.6 x Goals For + 5.40 x Shots on Target For + 0.24 x Total Shots For) – (10.50 * Goals Against + 0.14 x Shots on Target Against + 0.32 x Total Shots Against)

The R^2 between Team Rating this season and Team Rating next season is 0.603, and this seasons Team Rating predicts next seasons points with a Standard Deviation of 10.40 points, and a Mean Average Error of 8.21 points (all of n = 119)**. As for the Premiership Team Rating I’ve then re-scaled the values linearly on to a 0-10 scale, with the minimum and maximum Team Ratings in the sample being assigned 0 and 10, respectively.

Onto the results. Benitez took over from Mourinho who had won Serie A in the prior two seasons, despite maybe not having the underlying numbers to do so. In addition Mourinho had also won the Coppa Italia and the Champions League in his second season. Benitez lasted half of the season, and Inter bounced immediately back to their level under Mourinho when Benitez left.

Screen Shot 2015-06-02 at 9.36.39 AM

Inter fell off a cliff the last two seasons, but given the turnaround when he left I don’t think we can attribute any of that to Benitez not being there.

Finally we have Benitez’s current team – Napoli. Their Team Ratings for Benitez’s tenure, along with the two seasons prior are plotted below:

Screen Shot 2015-06-02 at 8.48.00 AM

There’s not really a ton to say here. Napoli have had the 3rd highest Team Rating in Serie A in each of the past four seasons, finishing 5th, 2nd, 3rd, and 5th over that span. Whilst Napoli haven’t been able to break into the top 2, it’s also true that no team since at least ’05-06 has scored as many as Napoli did in ’13-14 (78) whilst finishing 3rd in Serie A. Also, Benitez inherited a pretty good team but has kept them playing to that level, which isn’t necessarily easy and deserves some credit in and of itself.

In all, I still think Benitez is a perfectly good manager. One who turned Liverpool into a really good team, stopped the bleeding at Chelsea, whilst maybe not improving them as much as could have been done, had a really poor spell at Inter, and that, whilst he hasn’t been able to push Napoli into the very top tier in Serie A, he has at least kept them running in place, which shouldn’t be written off. On the other hand I don’t think this piece provides evidence to suggest that he’s one of the two or three best managers in the world, which is what Madrid should be looking for.

*I would have included the more seasons but it looks like a different data provider was used before 2007-08.

**As a comparison the equivalent numbers for the Premiership Team Rating are a little better, with R^2 = 0.796, STDEV = 9.56, MAE = 7.67 (all n = 221).

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3 thoughts on “On Rafael Benitez in the Premiership and Serie A

  1. Great post, James.

    Also, good to see some numbers on Serie A which, IMHO, is a bit neglected by the analytics community.

    And good spot on the FootballDataUk data before 2007/08: thet way total shots were calculated was significantly different.

    Also, I noticed that there’s a spike in correlation between points and shot-based metrics starting from the 2010-11 season which makes Seria A R2 more close to EPL’s.

    I wonder whether it’s just variance or something in Serie A’s game changed or, again, if there was a change in the data provider.

    Keep up the good work.

    Raffaele

  2. Hi Raffaele – thanks. If there’s anything else you’d be interested in give me a heads up and I’ll see what I can do.

    I’m not really sure what to think of that. The shot counts, proportion of shots that are on target, and the shooting percentages are really steady (though sh% appears to be creeping up) I’m wondering if it’s maybe just variance.

  3. Thanks James,.

    I’ve been planning to replicate your original Team Rating for Serie A and I’m working on it in my spare time

    So if you ever come up with the Serie A’s specific coefficients for each block of games and you publish them, that would be really awesome.

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