The 20-year-old right-back came to Carrington after getting permission from his club Penarol to make the trip.
And he admitted that he enjoyed his surprise trip after having a successful week training with the players.
Speaking to Tirando Paredes, Varela said: “I have trained with the first-team. I am very happy and I was received very well.
“It was a surprise to get the chance to test with Manchester United. I’m glad and happy, and grateful to Penarol who allowed me to travel.
“I was treated so well and Chicharito [Javier Hernandez] helped me a lot. The work outs were short but very demanding.”
Varela joins the likes of Jurgen Damm and Jeffrey Schlupp who have all enjoyed successful trials at the club and like his South American counterpart Damm, Varela admitted that Chicharito helped him a lot during the week.
It is a testament to the approachable attitude of Hernandez who really is a players’ player, happy to help out even with a youngster who is only with the club for one week.
Considered a real prospect back in Uruguay, Varela is expected to represent his country at the U20 World Cup this summer.
Diego Forlan is the only other Uruguayan who has played for Manchester United and he didn’t have the most successful time despite scoring some crucial goals, none more so than his winner against Liverpool that ‘made the Scousers cry’.
But given his prospects, maybe Varela could become the second to represent United under new boss David Moyes when he takes over from the club in the summer.