The Belgian playmaker has been in fine form for the Blues so far this term and he has scored five goals and made two assists in the Premier League.
Hazard was the star of the show on Saturday as he scored a hat-trick to help Chelsea FC to claim a 4-1 win over Cardiff City at Stamford Bridge in the Premier League.
That win lifted the Blues to the top of the Premier League table on goal difference after their strong start to the campaign.
Hazard, 27, will be aiming to keep his form up as he bids to try and help Chelsea FC to challenge for the Premier League title this season.
And Redknapp believes that new Chelsea FC boss Sarri deserves credit for the way he has been able to manage Hazard so far this term.
Speaking in an interview with the Daily Mail, Redknapp said: “This was Hazard’s first hat-trick for Chelsea since a 3-0 win over Newcastle in February 2014.
“Ronaldo and Messi have scored them at will throughout their careers. Maurizio Sarri has used him intelligently, first as an impact substitute before restoring him to the starting XI.
“It means that in Hazard’s mind he has had a break after the World Cup and is raring to go. The challenge for him now is to have a season like Mo Salah last year and get 40-odd goals.”
Chelsea FC will kick off their Europa League campaign with a trip to PAOK on Thursday night.
The Blues finished in fifth place in the Premier League and won the FA Cup under Antonio Conte last term.
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