Gianfranco Zola believes Eden Hazard has yet to reach his full capacity will improve a more potent force under the direction of Maurizio Sarri.
After an impressive World Cup, Hazard has made a strong start to the new campaign at Chelsea.
The 27-year-old Belgian striker has scored five goals in the Premier League and has been hailed by his new manager as the best player in Europe.
'He is a player who is getting better and better,' said Sarri's assistant Zola. 'I don't think he has reached his full potential.
'He can still use his skills in a better way. I truly believe this. And this year, the team, and Maurizio in particular, will help him to reach his full potential.
'I don't it want to look like we're not happy, we're very happy with him but as you play, you get more experiences, at a high level for a long time, you get better and learn how to use your abilities in a more efficient way.
'He will do it himself and we will try and suggest how to be more effective on the pitch, and he will benefit from the way we try to play.
'We try to play a long time in the opposition half. The closer we keep him to the goal, the more chances we can get him receiving the ball around the box and the more effective he will be.
'I would have enjoyed a lot playing in Maurizio's team. We play the majority of the games in the opposition's half. You get a lot of touches of the ball, especially our strikers. With my qualities would have enjoyed it very much.'
Hazard may not start in the Carabao Cup third round tie at Liverpool, on Wednesday, as Sarri tries to give fringe players some action and rest first-teamers for Saturday, when Jurgen Klopp's team are at Stamford Bridge, in the Premier League.
Gary Cahill could return, just days after declaring his intention to seek a move away from Chelsea in January if he was not in the team.
David Luiz and Antonio Rudiger have been Sarri's first-choice central defenders but Rudiger was injured during the goalless draw at West Ham on Sunday and will not travel to Merseyside.
Cahill made his first appearance of the season when he came on to replace Rudiger.
'It's totally understandable that Gary is upset,' said Zola. 'We want him to be upset, it means he cares. But he's a top professional and is doing everything correctly. He just needs to be patient.
'He came back late [because he was at the World Cup] and the players were doing well. He will have his chances, and then it's down to him to take his chances in the best way.'
Zola is back Stamford Bridge 15 years after he made his last appearance as a Chelsea player, against Liverpool in the Premier League and learning fast from Sarri.
'For me, it's a new world,' said Zola. 'He opened a big world in front of me. I thought I knew a lot about football. I was wrong.
'It has been great as an experience. Plus I'm enjoying working with him as a person, and also his staff.
'We're working very well together. We need to continue to do that.'