Analysis - Italian football expert Adam Digby on Sarri

As we prepare to face Maurizio Sarri's Chelsea for the first time this season in a huge game at Wembley on Saturday, we asked Italian football expert Adam Digby to tell us about the 'Sarri Effect' and the impact the manager had particularly during his time at Napoli in Serie A before joining the Blues this summer.

Adam is an Italian football writer for FourFourTwo, Bleacher Report and more - and the author of 'Juventus: A History In Black & White'.

The Sarri effect

There is no denying the impact Maurizio Sarri has had on Chelsea since his arrival this summer. Appointed to the role at Stamford Bridge in July, the 59 year old travels to Wembley this weekend with his new side still undefeated and within striking distance of first place in the Premier League.

With eight wins and four draws in his first 12 games in the English top flight, Sarri has also steered the Blues to victory in each of their first four Europa League outings, earning widespread admiration for the aesthetically pleasing style he has already imprinted upon his team.

Yet this is nothing new for fans of Italian football who watched Sarri do exactly the same at previous club Napoli. Moving to the Stadio San Paolo was his first shot at the big time, famously beginning his career in the lower leagues while still working at a bank, forced into giving up his day job when he needed to become a full time Coach.

He only experienced Serie A football for the first time in 2014/15 with Empoli, his time there enough to see him succeed Rafael Benitez at Napoli for the following campaign. While the Spaniard might have had a far superior reputation and certainly boasts much more silverware, it was Sarri who transformed the Partenopei almost instantly.

Sarri football

Engraining a possession-based style into an almost unchanged squad, clips of 'Sarri Football' soon went viral, constantly weaving intricate patterns with breath-taking short passes that carved open opposition defences. Napoli had finished fifth in their final season under Benítez but the new boss helped them to second, then third before last season becoming the first club to fail to win Serie A despite breaking the 90-point barrier.

They scored goals at an unprecedented rate, but it was arguably his work at the other end of the field that was most impressive. Eschewing the need for new signings, he took the same backline that was already in place before his arrival, leaving Sarri to drill his team meticulously and transform them into a formidable and compact unit that prompted former AC Milan manager Arrigo Sacchi to call the Napoli Coach 'an absolute master'.

It has been a similar story at Chelsea, Brazilian midfielder Jorginho moving alongside Sarri to help bring a similar style to Stamford Bridge. Just as the 'Mister' gave Dries Mertens and Lorenzo Insigne newfound impetus, Eden Hazard is once again back to his best as the focal point of the attack while Ross Barkley has made a remarkable return to form.

The SW6-based side dropped out of the top four last term, but the new boss has them shining with only Manchester City having scored more goals and Chelsea boast the third-best defence in the Premier League.

With six clean sheets already, they present a tough challenge for any attack as 'The Sarri Effect' is once again evident for all to see.