The Football Association is investigating allegations that Manchester City paid £200,000 to Jadon Sancho's agent when the player was 14.
German magazine Der Spiegel claimed City made the banned payment to agent Emeka Obasi in relation to the deal that took the youngster to the club from Watford in 2015.
Under Premier League rules, clubs are not permitted to offer financial inducements to a player under 16 or any person connected with that player.
An FA spokesperson said in a statement: "We can confirm that the FA will be investigating the allegations."
City responded to the claims on Friday, saying in a statement: "The attempt to damage the club's reputation is organised and clear.
"We will not be providing any comment on out of context materials purported to have been hacked or stolen from City Football Group and Manchester City personnel and associated people."
Emotional evening tonight making my full @England debut at Wembley and playing in front of my family! Good to get an assist and send off @WayneRooney with a win , true legend! 🏴🦁 pic.twitter.com/3WYbXF6MEE — Jadon Sancho (@Sanchooo10) November 16, 2018
Sancho did not made a first-team appearance for City and moved to German side Borussia Dortmund for £8million in August 2017.
One of the Bundesliga's outstanding players this season, the winger made his England debut against the United States in November.
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