Manchester City have signed 17-year-old winger Kayky from Brazilian club Fluminense for a fee believed to be worth around £9 million ($12m) plus add-ons.
The teenager is set to remain in Brazil until the end of the 2021 season before either moving to City or going out on loan.
Goal revealed in January that City were close to signing the highly-rated Kayky, who was also wanted by Ukrainian champions Shakhtar Donetsk.
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Who is Kayky?
Fully named Kayky da Silva Chagas and compared to Neymar, he only made his debut for the senior team this season but has been scouted by City for a number of years.