Defeat to Manchester United in the FA Cup saw the fans turn on him, something that is quite rare for Chelsea fans; that said, they don’t often get the chance to turn as Roman Abramovich is usually quick to remove a manager he has lost faith in.
This week, it has been claimed that if Sarri fails to avenge the City defeat by beating his good friend Pep Guardiola in the League Cup Final at Wembley on Sunday that he will be the latest manager to depart Stamford Bridge less than a season into his tenure.
But is Sarri doing any worse than he was at the same stage at Napoli?
After all, this is a manager that hasn’t won any silverware and it has been said over and over that Sarriball takes time to implement.
So, by comparing the stats from his Napoli side of 2015/16 to his Chelsea side of today we will learn whether Sarri is doing better than the results would suggest.
Our naked eye has to say that he is failing, but is that the case?
Let’s find out.
A lot of what Sarri is supposed to be bringing to Chelsea is based around what they do on the ball.
Sarriball is said to be vertical tikitaka, meaning the ball moves quickly forward with sharp passing combinations.
This is the part of Sarri philosophy that takes the longest to embed due to the need for many, many coaching hours.
So, it makes sense for us to compare the stats of both teams with the ball.
This image shows data collected from Wyscout and shows pretty much every facet of possession you can think of.
It is easy just to look at possession % or completed passes by 90, but I wanted to go a little deeper to see how effective the style of possession was being.
To the naked eye, it feels like Chelsea play a lot of lateral passes; moving the ball from side to side rather than forward.
The numbers back this up. Sarri’s Napoli side were playing more forward passes per 90 minutes in their first season than Chelsea are to date.
You can also see that Chelsea are playing more lateral passes than the Napoli side were.
Progressive passes and smart passes also interest me. As the names suggest, a progressive pass is said to be a pass that has the aim of progressing a move in a positive fashion and a smart pass is probably what the layman would call a clever pass, though this statistic is open to various interpretations.
Napoli were doing more than Chelsea in both areas at this point.
This again backs up the naked eye theory that Chelsea are not breaking teams down very easily.
Until Gonzalo Higuain signed for Chelsea, a lot of the narrative was based around them not having someone to finish the chances they were creating.
These next graphics look at how both teams compare in front of goal.
As you can see, Napoli were creating more opportunities than Chelsea at this stage.
That said, Napoli were overperforming on their xG whereas Chelsea are actually scoring at the exact rate the xG suggest they should be.
But in terms of shots on target and everything else, Napoli were more effective by this point.
Finally, I’d like to look quickly at both teams defensively. Chelsea, despite starting the season unbeaten for many games, have been defensively pulled apart in recent weeks.
As you can see, Chelsea are conceding more of everything than Napoli were over the course of 90 minutes.
So what does all this mean?
The aim of this piece was to see whether Sarri is on track with his Sarriball project at Chelsea given that we are always told that it takes time to implement.
The data tells us that his Napoli squad were picking up the concepts quicker than the current Chelsea squad.
In every key area, Napoli has better data than Chelsea.
If you think about progressive passing, can Sarri be at fault here? Well, possibly yes. He wanted Jorginho to play as the six, to be the player to coach his style of play to the team during the match. It was also Sarri’s decision to move N’Golo Kante into an eight; a position that Kante is doing OK at, but only OK. And one thing Kante is not is a progressive passer of the ball. At Leicester, his role was to be everywhere then give it to Danny Drinkwater who’d find Jamie Vardy. When Chelsea won the title, he did the same except this time he was giving it to Cesc Fabregas.
Did Sarri want Marko Kovacic? We don’t know, but he hasn’t been the consistent answer either.
If you then think about in front of goal, is it Sarri’s fault they’ve not been taking their chances?
Well, actually they have been. Chelsea have scored what their xG suggest they should have scored on average this season. Yes, there will be ups and downs per match, but this does not appear to be the problem.
Granted, bringing in Gonzalo Higuain gives Sarri a better option than Alvaro Morata and this could have a positive impact if everything behind him improves.
And defensively, I think Sarri has to shoulder some of the blame.
He has chosen to have a back four with David Luiz and Marcos Alonso in it as he feels they are the players that can play his style out from the back. The problem is, they have both been shown up as defensive weak links consistently this season, whilst the jury is also out on Antonio Rudiger.
Further analysis of these points would be interesting.
However, we don’t have time for that in this piece.
What will happen to Sarri? We don’t know, though it certainly would be a shock if Chelsea did beat Man City on Sunday and that is about the only thing that could guarantee he remains in employment.
The numbers don’t lie; they completely back-up the naked eye theory that Project Sarriball is not running smoothly or to time.