Chelsea have announced that defender Andreas Christensen has signed a new four-and-a-half-year contract.
The 21-year-old has committed himself to the Premier League champions until the end of the 2021-22 season.
Christensen's new deal comes as a reward for his strong performances under Antonio Conte this term.
"It feels really good to sign a new contract and I'm just happy to be committed to Chelsea for the future," the centre-back told the club's official website.
"I've played a lot of games, I'm enjoying it at the club and everything is working well."
Christensen signed in 2012 but spent two seasons on loan with Borussia Monchengladbach between 2015 and 2017.
The Denmark international has established himself as a key part of Conte's plans this term, though, making 22 appearances in all competitions.
Chelsea director Marina Granovskaia said: "This contract is reward for the excellent form Andreas has shown in the first half of the season. He showed immense potential when he signed for Chelsea in 2012 and is now enjoying the benefits of the dedication and professionalism he has shown since.
"After two seasons on loan in Germany, we were convinced he was ready to be a part of the squad this season and he has grasped the opportunity with both hands.
"We are delighted he has chosen to commit his future to Chelsea and we look forward to four and a half more successful years with Andreas at the club."
