The 18-year-old has been earning lots of praise as one of the Premier League’s top young talents since his arrival at Stamford Bridge from Exeter City last summer.
Ampadu made a handful of first-team appearances for Chelsea FC last season and caught the eye with some mature and impressive displays.
The defender was again in impressive form for the senior Wales team during the international break.
Ampadu has yet to make a first-team appearance for Chelsea FC under new boss Maurizio Sarri this term, but the Blues have moved quickly to tie the defender down to a new long-term deal.
And Chelsea FC chief Granovskaia has explained why the west London side have moved quickly to get the defender to commit himself to the Blues.
Speaking to Chelsea FC’s website, Granovskaia said: “Ethan has shown great potential and unbelievable maturity since arriving at Chelsea a year ago.
“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.”
Meanwhile, Chelsea FC are currently preparing for their Europa League opener against PAOK on Thursday night.
The Blues are top of the Premier League table after having won all five of their opening top-flight games under new boss Sarri following his appointment in July.
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