The France international has found himself frozen out of contention in west London and is heading back for a second loan spell with the Rossoneri
Chelsea and AC Milan have struck a deal that will see Tiemoue Bakayoko move to San Siro, Goal can confirm.
The midfielder has struggled to make an impact at Stamford Bridge since his arrival from Monaco, but did impress during a loan spell with AC Milan.
And he will now return to Serie A on an initial loan move that could become permanent further down the line.
Bakayoko will soon put pen to paper to seal his second spell with the Rossoneri.
The France international will at first move on loan in a deal that will last two seasons.
At the end of that spell, in June 2023, Milan will be obliged to purchase Bakayoko, as long as he meets certain playing-related conditions specified by the two clubs in their agreement.
Chelsea hope to recoup €20 million (£17m/$24m) in the future sale, and will extend his contract to June 2024 this week in order to avoid losing him on a free at the end of his current deal.
Bakayoko came highly rated when he swapped Monaco for west London in 2017, with Chelsea shelling out around £40m to make him the club's then-second most expensive signing of all time, behind Fernando Torres.
But he failed to match initial expectations, enduring a disappointing debut season and leaving for Milan on loan at the start of 2018-19 - where he eventually found his feet after a similarly rough start.
Further temporary moves followed in the next two seasons, at Monaco and Napoli, as it became clear there was no room for him at Stamford Bridge.