The Belgium international has made an impressive start to the Premier League campaign following a return of five goals in six outings in the current season.
Hazard scored an 85th minute winner to secure a 2-1 win over Liverpool FC in the Carabao Cup third round ahead of their meeting in the Premier League this weekend.
The 27-year-old has been one of the Premier League’s top performers since his move to Chelsea FC from Lille in 2012 under Rafael Benitez, Jose Mourinho, Antonio Conte and now Sarri.
Under Mourinho and Conte, the Belgium international was forced to carry out his defensive duties to hamper his ability to affect games further up the pitch.
Sarri, though, has allowed Hazard to play with more freedom and the decision has paid dividends given his prolific start to the 2018-19 Premier League season.
Speaking at his pre-match media conference ahead of Chelsea FC’s home clash against Liverpool FC at Stamford Bridge on Saturday evening, Sarri believes there is much more to come from Hazard.
“I think that he’s for sure one of the best but I’m absolutely convinced that he can improve,” Sarri said.
“If he can improve during training maybe he will be able to use and serve at 100 per cent. Because I think that we have seen only 70-80 per cent of his potential, so if he can improve he can be the best in the world.
“It’s difficult to compare him with other players. He’s a genius, I think he’s unique.”
Liverpool FC finished in fourth spot narrowly above Chelsea FC in the Premier League table.
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