The Blues forward has made a scintillating start to the Premier League season under new Chelsea FC manager Maurizio Sarri.
Hazard netted five times in five games in the English top flight to help the Blues secure top spot in the table.
However, Chelsea FC dropped down to third place following a goalless draw with West Ham United at the London Stadium last weekend.
The Blues forward scored 16 times in Chelsea FC’s title-winning campaign in 2017-18 but Hazard has never scored more than 20 goals.
Chelsea FC will host Premier League leaders Liverpool FC at Stamford Bridge on Saturday evening in the top of the table clash.
Former Manchester United defender Neville believes Hazard will need to score at least 40 goals this season for Chelsea FC to challenge for the title.
Neville told BBC Sport: “Hazard will have to score 40 goals this year for Chelsea to get close to actually challenging for the league. If he doesn’t, then they’ll struggle to get into the top four.”
Chelsea FC finished in fifth spot in the Premier League table last term to miss out on Champions League football for the second time in three seasons.
The Blues have beaten Huddersfield Town, Arsenal, Newcastle United, Bournemouth and Cardiff City in the title race so far.
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