Kurt Zouma will undergo knee surgery this week which will rule him out for the rest of the season and Euro 2016, Chelsea have announced.
The France defender injured his anterior cruciate ligament in Sunday's 1-1 Premier League draw with Manchester United.
A statement on Chelsea's official webiste said: "Kurt will undergo surgery in the next 48 hours and is expected to be out for approximately six months."
The news comes as a huge blow to both club and country.
Chelsea are currently in the process of reviving a wretched season under stop-gap manager Guus Hiddink and they retain outside hopes of making next season's Champions League through a top-four Premier League finish.
France host this summer's Euros and they will want to put in a strong showing on home soil.
Scan today has shown I injured my ACL. I will have surgery this week & will come back stronger. Thank you everyone for all the messages 🙏🏻🙏🏻— Kurt Zouma (@KurtZouma) February 8, 2016