The Belgium international has made a bright start to the Premier League campaign following Sarri’s appointment as Antonio Conte’s successor.
Hazard scored seven times in eight games in the Premier League before the Blues forward suffered an injury during a 2-2 draw with Manchester United last month.
The 27-year-old made his first start since recovering from his injury in a 0-0 draw with Everton in the last round of Premier League fixtures before November’s international break.
Hazard has won two Premier League titles since his move to Chelsea FC in a lucrative deal from Ligue 1 side Lille in the 2012 summer transfer window.
However, the Belgian star has struggled to produce consistent performances throughout successive seasons, tending to drop off after title-winning seasons.
The Blues suffered a 3-1 loss to Tottenham at Wembley on Saturday evening to fall seven points adrift of leaders Manchester City.
Former Chelsea FC striker Hasselbaink believes Hazard needs his other team-mates to step up if the Blues are going to challenge for silverware in the current campaign.
“For me it’s a very bad thing if you become a one-man team,” said Hasselbaink, speaking exclusively to 888sport.
“Hazard is magnificent and has been exceptional but if you look at last season with Liverpool, Salah scored so many goals and they became a one-man team as well. They didn’t win anything.
“If you are a one-man team you won’t win any trophies so others are going to have to step up. They have to step up and help him.”
Chelsea FC finished in fifth spot in the Premier League table last term to miss out on a place in the Champions League for the second time in three seasons.
Sarri signed Mateo Kovacic, Jorginho, Rob Green and Kepa Arrizabalaga in the 2018 summer transfer window.
Read the full 888sport interview with Jimmy Floyd Hasselbaink including his thoughts why it’s Chelsea, not Liverpool, who are Manchester City’s biggest title rivals this season.
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