Penarol youngster Valera moves to Old Trafford for undisclosed fee.
Manchester United have completed the signing of Penarol right-back Guillermo Varela on a five-year deal.
The Uruguayan youngster is the first signing of the David Moyes era after the Scot succeeded compatriot Sir Alex Ferguson at Old Trafford last month.
“I’m very pleased to be a part of this club, one of the best teams in the world,” the 20-year-old told United’s official website.
“As everyone in the world knows, this is a huge club that has won everything and I really hope that continues.”
Varela joins fellow South Americans Antonio Valencia, Anderson, Rafael, Fabio, Angelo Henriquez at Old Trafford and will be the eleventh South America to represent the Premier League champions should he make an appearance next season.
The defender believes the amount of native Spanish speakers in the squad will ensure he settles quickly in Manchester ahead of the new season.
“I’m very lucky there are quite a few Spanish-speakers here,” Varela added. “It will certainly help me settle in.”
Varela impressed during a week’s trial at United’s Carrington training ground under the watchful eye of Ferguson and has shone for Uruguayan in qualifiers for the under-20s World Cup.
Brazil international Rafael was United’s first choice right-back last season, although versatile Englishman Phil Jones and Chris Smalling can also operate at full-back.