Manchester United boss Sir Alex Ferguson has confirmed Antonio Valencia has flown back to England for treatment on his ankle injury.
Valencia will play no part in United's pre-season tour of the United States after picking up the injury while on international duty with Ecuador at the Copa America.
United are optimistic that the injury is not serious, but Ferguson is refusing to take any risks with the winger after he missed a large chunk of last season with a serious ankle problem.
"Antonio has gone straight back to Manchester," said Ferguson after the 4-1 win over New England Revolution in Boston.
"He got an injury playing in the first game for Ecuador so he is back in Manchester.
"It is nothing serious but he wasn't going to be taking part in the rest of Copa America, so there is no point in him coming out here if he is injured.
"We have the facilities back at Carrington. That is the best place for him."
United's win over New England saw Ashley Young make his debut for the club and Ferguson was happy with the England's international bow in a wide role.
"That was his position until last season when they started playing him behind the strikers in a more advanced role, like the way we use Wayne Rooney," added Ferguson.
"His capabilities are such that he can play at wide left, he can play in behind the strikers and he can play wide right.
"He showed tonight he's a fantastic crosser of the ball. I think he hit three fantastic crosses in the game, which maybe isn't something we're used to with the way we play.
"But if we do get used to it then there's goals there. I was very satisfied."