The Argentina global set a new Serie A goal-scoring record under Sarri at the Stadio San Paolo in the 2015/16 campaign with 36 goals.
Higuain is now on loan to AC Milan from Juventus, but the Rossoneri are reportedly ready and willing to let the 31-year-old end his spell early as they are struggling to pay his hefty wages.
"Gonzalo has lived through this moment but now he has to leave it behind him".
He said: "A goal can change things, but if he is to continue here, he needs to take on responsibility".
Brazilian Leonardo added: "There's no point following rumours and gossip".
Chelsea's strikers aren't doing too good this season, either.
However, negotiations are complicated and the two parties (Chelsea and Juve) have different ideas: the Bianconeri wanting the Premier League side to basically accept the same terms as Milan - a loan with €36m obligation to buy.
As well as Higuain, Chelsea are believed to be keeping tabs on Bournemouth's Callum Wilson, who was a reported £50 million price tag.