The Belgium international has made an incredible start to the Premier League season despite the change of manager in the summer.
Sarri has given Hazard the freedom to play in a more advanced role and the move has paid dividends given the Belgian’s prolific form.
Hazard broke the deadlock and created Ross Barkley’s goal in a 3-0 win over Southampton at St Mary’s in the Premier League on Sunday afternoon.
The Chelsea FC number 10 has scored seven goals in eight games in the Premier League, which is his best-ever start to a season in the English top flight.
Hazard has also created three goals for his team-mates to help the west London side win six times and draw twice to make an unbeaten start to the season under Sarri.
However, former Spurs forward Crooks is concerned that Chelsea FC have become too reliant on the 27-year-old.
“Yet another masterclass from Hazard against Southampton,” Crooks told BBC Sport.
“Without doubt the best player in the Premier League and on current form arguably the best player in Europe.
“The only problem Chelsea face is what happens if they lose the Belgian through injury? There is a feeling the Blues may be a tad over-reliant on him.”
Hazard’s long-term future at Chelsea FC remains unclear given the Belgian star hasn’t signed a new contract with the west London side.
The former Lille winger has less than 24 months left to run on his current deal with the Stamford Bridge outfit.
Hazard could leave in a cut price deal next summer if Chelsea FC opt to cash in on their star man rather than lose the winger for nothing at the end of the 2019-20 campaign.
Indeed, Chelsea FC were in a similar situation with Thibaut Courtois in the summer and decided to sell Real Madrid in the most recent transfer window rather than lose the goalkeeper for nothing next summer.
The Belgian star has made no secret of his affection for Real Madrid, although his football idol Zinedine Zidane departed the La Liga side in the summer.
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