The Belgium international scored one goal and made an assist in Chelsea FC’s 2-1 win against Brighton and Hove Albion at Amex Stadium earlier in December to score for the first time in eight league games.
The number 10 failed to get on the score sheet in a 1-0 loss to Leicester City at Stamford Bridge on Saturday evening.
Hazard has netted eight times and has made nine assists in 17 Premier League games this season to lead the Chelsea FC goal-scoring charts.
The 27-year-old scored seven goals in his opening eight appearances in the Premier League to prompt Sarri to challenge Hazard to score 40 goals or more this term.
However, Hazard suffered an injury problem in a 2-2 draw with Manchester United at Stamford Bridge and the Belgian forward lost his early-season momentum.
German defender Rudiger believes Hazard will find it difficult to match Sarri’s expectations in the Premier League this season.
“He is human, of course he is,” Rudiger is quoted as saying by The Sun.
“But the way he is playing is fantastic, we all know what he is capable of. I am happy that he scored.
“He is a leader. He provides a good example, not by speaking but by showing. He gets kicked often, because he is good.
“With respect to the others, I think in the Premier League they are not stupid players, so to reach 40 goals? Maybe he can do it.
“But what he does is OK. We need to respect the other teams, it’s not like they are bad or something.
“He does not have too much of an ego. If he sees other players standing in a better position, he plays them in.”
Hazard moved to Chelsea FC from Lille in the 2012 summer transfer window after the Belgium international opted to move to Stamford Bridge ahead of Manchester City and Manchester United.
The Chelsea FC star has won two Premier League titles, the Europa League, the FA Cup and the League Cup during his spell at the west London outfit.
The Champions League crown has eluded Hazard at Stamford Bridge after Chelsea FC won the competition in May 2012 ahead of his arrival.
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