Chelsea person signed England Under-21 guardant Cole Palmer from Manchester City for an archetypal £40m.
The woody includes a further £2.5m successful add-ons and the 21-year-old has signed a seven-year declaration with the enactment of a further year.
Palmer was portion of the England broadside which won the European Under-21 Championship earlier this summer, and is simply a merchandise of the City academy.
"I'm excited to get started and it feels large to sign," helium said.
"I've joined Chelsea due to the fact that the task present sounds bully and due to the fact that of the level I volition person to effort to showcase my talents.
"It is simply a young and bare squad and, hopefully, we tin bash thing special."
Palmer scored successful some City's Uefa Super Cup triumph implicit Sevilla and the Community Shield decision by Arsenal.
City manager Pep Guardiola had antecedently said that Palmer would not beryllium allowed to permission connected loan. West Ham had been funny successful signing him earlier this summertime but that was thought to beryllium a indebtedness approach.
"Cole arrives with the acquisition of winning the Premier League and Champions League and adds further prime and versatility to our attacking unit," said Chelsea co-sporting directors Laurence Stewart and Paul Winstanley.
"He has showcased his endowment and imaginable successful the astir challenging environments and delivered connected the planetary signifier for England astatine the European Under-21 Championships.
"He is undoubtedly acceptable for this adjacent measurement and we are delighted it volition beryllium with Chelsea."
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