Eden Hazard is among the best players in Europe but can add more goals to his game to rival Lionel Messi and Cristiano Ronaldo among the elite, according to Maurizio Sarri.
Hazard has been linked with a move to Real Madrid to replace Ronaldo after the Portugal superstar left the Spanish capital to join Serie A champions Juventus in a deal worth €112million.
Sarri is confident Hazard will stay at Chelsea, who would be unable to sign a replacement for the Belgium international due to the Premier League's transfer window closing last week.
And the new Chelsea head coach feels there is still more to come from Hazard, who has hit at least 12 Premier League goals in four of the past five seasons for the Blues.
"Hazard, technically, is really one of the best in Europe in this moment, I think," Sarri told reporters. "He has to work from the physical point of view, of course.
"It depends on his position on the pitch. In the last five years, Cristiano has played like a striker. Messi like a striker, Eden sometimes like a winger. Eden can improve.
"We are talking about one of the most important players in Europe now but, in my opinion, he can improve more. He can be the first. It depends on him. The best for technical skill, the best for scoring, but I think it depends only on him. On his mind.
"Chelsea are one of the most important clubs in Europe. I think one of the most important clubs in Europe cannot sell an important player without the possibility of buying a player on the same level.
"The first time I have spoken to him, I was sure that he would stay. So I was concerned for 20 days, no more."
Chelsea take on Arsenal in the Premier League's game of the weekend on Saturday and Sarri expects the Gunners, also under new leadership in Unai Emery, to rival his team for a place in the top four.
"Arsenal can be, for us, a direct opponent for the target of the club. Of our season. A direct opponent for a place in the Champions League, I think," Sarri said.
"We can finish above or below them, I don't know, but I think they will be competitive for a place in the Champions League.
"It's not easy, of course. But I think this coach has the ability to start a new era. He won three times the Europa League, and won in France, so we're talking about a very good coach. I think that, in pre-season, they have played well.
"Arsenal, this season, can improve and be competitive, and can fight for a good position."
