United have reportedly agreed terms with the La Liga club which removes the need for UEFA to intervene on the cost of any deal for the 16-year-old.
The youngster caught the eye of the Old Trafford hierarchy after notching 60 goals for Zaragoza’s youth team and has been a United player since July, according to El Periodico de Aragon.
Zaragoza previously denied that their promising forward had moved to England, but reports now suggest that their resistance was broken and he has made the move to Old Trafford.
Real Madrid had held an interest in the player – who usually plays on the right wing – but Zaragoza rejected a £431,000 offer from Los Blancos.
Because he had not signed his first professional contract yet, Mejia was able to negotiate with teams outside of Spain without a fee needed.
United understood that the eventual amount would be decided by a UEFA tribunal but managed to negotiate with Zaragoza without the governing body’s intervention.
He joins former Monaco starlet Hannibal Mejbri and Noah Emergan as promising youngsters to join the club.
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