The Spain international is thought to be closing in on a move to Ligue 1 side AS Monaco from the Premier League side after falling down the pecking order at the west London side.
Fabregas looks set to reunite with his former Arsenal team-mate Thierry Henry, who is currently in charge of AS Monaco following his appointment last year.
Chelsea FC have been linked with a move to sign Cagliari midfielder Nicolo Barella and Zenit St Petersburg playmaker Leando Paredes.
The Blues have already signed Borussia Dortmund playmaker Christian Pulisic in the January transfer window but the £58m signing was loaned back to the German club for the remainder of the current campaign.
Asked about signing Barella to replace Fabregas, Sarri refused to name any specific targets but indicated that Chelsea FC would look to fill the Spanish midfielder’s void.
“I don’t want to speak about players of other teams,” Sarri said when asked directly about Barella at a news conference at Cobham on Monday afternoon.
“If Cesc wants to go then we need a replacement. I don’t know the situation of Loftus-Cheek, if it is serious. Without Cesc we are only five, we need a replacement.”
Chelsea FC are in fourth place in the Premier League table following a strong start to Sarri’s first season in charge of the west London side.
The Blues are three points ahead of Arsenal ahead of their home clash against Newcastle United at Stamford Bridge in the Premier League on Saturday evening.
Chelsea FC became the first team to beat Manchester City this season when the Blues were 2-0 winners in west London back in December.
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