Christensen, 21, has established himself as an important member of Antonio Conte’s squad this season, making 22 appearances so far and impressing with his assured displays at the centre of defence.

The defender, whose new contract will keep him at Stamford Bridge until 2022, said: ‘It feels really good to sign a new contract and I’m just happy to be committed to Chelsea for the future. I’ve played a lot of games, I’m enjoying it at the club and everything is working well.’

Club director Marina Granovskaia added: ‘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.’