The Red Devils were credited with an interest in the 17-year-old earlier this year after the Cerro Porteno wonderkid caught the eye when representing his nation at this year's South American Youth Championship.
United to miss out on 'next Aguero'
The teenager has been dubbed the 'next Sergio Aguero' due similarities in the way Perez plays the game and his physical attributes, and United were said to be interested in a deal as they look to bolster their strikeforce.
However, Goal Brasil are reporting that Roma have already agreed a deal in principal with Perez to take him to Europe when he turns 18, offering his club seven million euro up front, with bonus payments potentially taking the transfer beyond the 10million euros mark.
Should the Italians negate on the agreement then Cerro have said they expect Diaz to join another of Europe's big clubs, giving United hope he could still make the move to Old Trafford.
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