Ethan Ampadu has signed a new contract committing him to Chelsea until June 2023, the Premier League leaders have announced.
Despite only turning 18 this month, Ampadu -- who is equally comfortable in central defence or central midfield -- is already a senior Wales international and has appeared for Chelsea's first team on seven occasions since making his breakthrough under Antonio Conte last season.
"I'm really proud and happy," Ampadu told Chelsea's official website after signing his extension. "I'm looking forward to the next five years and all I have got to do now is continue to work hard, and hopefully good things will happen."
Chelsea director Marina Granovskaia was equally as pleased.
"Ethan has shown great potential and unbelievable maturity since arriving at Chelsea a year ago," she added. "In this short time he convinced a lot of people with his exceptional quality and mentality and we look forward to watching him develop into a key player for the club over the coming years."
The son of Arsenal coach and former footballer Kwame Ampadu, he made his Chelsea first-team debut within months of arriving at the club from Exeter City in July 2017, coming on in the second half of a Carabao Cup third round tie against Nottingham Forest at Stamford Bridge.
Chelsea's belief in Ampadu's ability was underlined earlier in September when he was among those included in the club's Europa League squad at the expense of Danny Drinkwater, a £30 million signing from Leicester City in the summer of 2017.
Ampadu is one of the talented youngsters expected to be involved in a match day squad for the first time under Maurizio Sarri when Chelsea begin their Europa League campaign away to PAOK Salonika on Thursday, along with winger Callum Hudson-Odoi and goalkeeper Marcin Bulka.