Manuel Ugarte has undergone surgery after suffering a knee injury at the World Cup, Manchester United have confirmed.
The midfielder was stretchered off during Uruguay's final group game with Spain.
Ugarte posted on social media that he had suffered "the most serious injury a footballer can face."
Medical tests revealed a knee ligament injury which has required an operation.
A statement issued by United on Wednesday read: "Manchester United can confirm that Manuel Ugarte has undergone successful surgery to address a knee ligament injury, which he suffered whilst representing Uruguay at the FIFA World Cup.
"Ugarte will now begin the rehabilitation stage of his recovery and will be carefully managed by the club's medical and performance staff.
"Everyone at Manchester United wishes Manuel well for his recovery and will be supporting him every step of the way."
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United had been open to offers for Ugarte this summer, but any transfer is now off with the 25-year-old expected to miss the majority of next season.
Andrey Santos and Youri Tielemens have arrived at Old Trafford to bolster Michael Carrick's midfield.
United have not ruled out making a third midfield signing in the wake of Ugarte's injury.