Bakayoko is set to join the italian side on loan.
The 23-year-old attended the Rossoneri’s La Madonnina clinic on Monday and is expected to sign a contract with the club once the checks are completed.
The France international will reportedly join on a season-long loan deal, with Milan retaining the option to sign him permanently in 2019 for a fee of €35million.
Bakayoko signed for Chelsea from Monaco last July in a deal worth in the region of €45m, but he struggled badly in his first season in the Premier League.
However, David Luiz appears more likely to stay at Stamford Bridge after Sarri backed him to play an important role this term.
“I don’t know about what happened in the past but now he has a good chance,” Sarri said of the Brazil defender. “We only have to carry on like we are doing now with him.”