Chelsea have completed the signing of Mamadou Sarr from Ligue 1 side Strasbourg for an undisclosed fee.
The teenager has signed a long-term contract with Chelsea that will run until 2033. Sarr impressed as part of a Strasbourg side that finished seventh in France to secure European football for next season.
Welcome to Chelsea, Mamadou Sarr!  🔵
— Chelsea FC (@ChelseaFC) June 9, 2025
The 19-year-old made 28 appearances in all competition in a breakout campaign for the centre-back. Sarr joined Strasbourg from Lyon for a fee of €10m last summer, having made just three senior appearances for the club.
He has been capped for France at various age groups and was part of the u-17 side that won the European Championship in 2022.
Sarr becomes Chelsea’s second signing of the summer window, following the £30m arrival of Liam Delap from Ipswich Town. Both players are expected to join up with Enzo Maresca’s squad for this summer’s Club World Cup in the United States.
Sarr will be joined by some familiar faces in West London, with Chelsea duo Djordje Petrovic and Andrey Santos having spent the 2024/25 campaign as teammates of Sarr on loan at Strasbourg. The French side are owned by the consortium called BlueCo, who also own Chelsea.
Read –Â Midfield Magicians: Wesley Sneijder, fleetingly great
See more –Â Jamie Gittens: Why Chelsea want to sign the Dortmund winger