"Chelsea have an agreement with Higuain to take him immediately", Gazzetta reported.
Higuain enjoyed his best run of form under Sarri, scoring 37 goals with the Italian boss prior to moving to Juventus.
Higuain's current sporting director has challenged his striker to improve at Milan, with a move to Stamford Bridge looking increasingly unlikely.
'He had a tough moment, he has to put it behind him and get to work.
Chelsea head coach Maurizio Sarri's first-choice preference to add firepower to his squad is thought to be Juventus striker Gonzalo Higuain, who is now on loan at AC Milan.More news: 'Project CARS' Developer Announces New Mad Box Console
"This deal is complicated as when Milan took him on loan from Juventus, they paid a £16million loan fee and agreed to buy him outright for £32m in the summer".
Higuain sent out on loan to AC Milan last August after the arrival of Cristiano Ronaldo and the Argentine has been unable to find his footing at the club.
When asked about Chelsea's interest in Higuain, Leonardo said: "There's no point following rumours and gossip".
The Argentine frontman bagged a stunning 36 Serie A goals from 35 appearances under Sarri's tutelage in the 2015/16 campaign. Seeing as he is here, he needs to get down and actually do something for this team.
Chelsea's strikers aren't doing too good this season, either.
Chelsea will allow Alvaro Morata to leave Stamford Bridge this month if they can secure a replacement, with Sevilla now making their interest in the striker public.