Sarri became Chelsea manager over the summer, replacing Antonio Conte at the helm at Stamford Bridge.
He has led the Blues to an unbeaten start in the Premier League while the west Londoners have also won two from two in the Europa League.
Sarri has been assisted by Chelsea legend Zola with the pair’s relationship appearing to flourish.
And the former Blues forward has explained how Sarri gets the best from his players.
“It’s a lot, the level of details that he puts,” Zola said. “He really doesn’t leave anything by chance.
“So when the players go out on the pitch the players know everything about what they have to do and that’s a big help.
“He’s obsessed with knowing everything about the opposition and then going to the pitch to prepare everything.
“He knows player by player. All the key players of the opposition, how they defend, how they attack and so therefore doing everything to stop them from playing and playing around them, there is a lot of work.”
And Zola isn’t left out when it comes to grafting.
When asked if Sarri gives him homework, Zola laughed and said: “I can not stop, I am watching more games in the last two months than in the last five years.”
Eden Hazard has shone under Sarri, bagging seven Premier League goals.
And the Belgian praised the former Napoli manager for the style he has adopted at Stamford Bridge.
“The more you have the ball the more you have chances to do something,” Hazard told The Times.
“If I touch 40 balls in one game it’s not easy to do something but, if I touch 90 balls, I have more chance to create something.
“My football is always like this, I take a risk, I try to dribble [past] one, two sometimes three, I miss sometimes but sometimes I can pass players and score goals.
“[The attention] it’s good for me.
“Since the FA Cup final last year [won courtesy of a Hazard penalty], the World Cup, I’m at a good level, I can score goals and, when you do something good, you need to practise more to keep this good momentum.
“I’m in a good mood at the moment. I just want to keep going like this.”