The New England Revolution midfielder is a permanent U.S. resident but has not yet received American citizenship.
Fagundez has accepted a call-up from the Uruguay Under-20 national team for a pair friendlies against Peru next week, the Revolution announced Friday. Fagundez previously was called up by the South American nation's U-20s in October 2012.
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Because Fagundez is not yet an American citizen, he will lose any chance of representing the USA if he does play for Uruguay in a competitive youth national team match. The soonest that can happen is January, when Uruguay will host the South American U-20 championship.
The 19-year-old, who was born in Uruguay but moved to the USA as a child, will travel to Lima on Sunday and return to the Revolution on Aug. 8, meaning he will miss no MLS action. The Uruguay U-20s will face Peru on Monday and Wednesday.