Marcos Rojo played his first ever Manchester derby on Sunday but was unable to see out the match as the player had to be stretchered off eight minutes into the second half.
Undeniably in great pain when he went off manager Van Gaal later confirmed that the 24 year old had dislocated his shoulder due to a heavy fall after a collision with an opposition player.
Rojo was replaced by teenager Paddy McNair minutes before City scored and the Argentine is not expected to return in time for United’s next match against Crystal Palace.