Manchester City are set to get at least £10m after Romeo Lavia completed a £58m move to Chelsea on Friday.
The 19-year-old spent the 2022/2023 campaign at Southampton.
Lavia stood out in what ultimately proved to be a miserable season for the Saints as they suffered relegation.
The Belgian has now made a return to the Premier League with Chelsea.
However, the Blues’ acquisition will benefit their rivals City.
The Premier League champions included a 20% sell-on clause in the transfer package that saw Lavia join Southampton in 2022.
City always rated Lavia highly, but fierce competition for places at the Etihad Stadium meant that he had to look elsewhere for regular game time