Louis van Gaal has said that he is still figuring out what type of player he needs to buy to improve Manchester United's squad this summer.
The manager took over the side following the conclusion of the World Cup earlier this month, and has only seen his players perform in two pre-season friendlies so far.
He told Sky Sports News: "I don't buy players for the sake of it. I buy players to improve my selection.
"First, I must see what I need in all the positions from the system we shall play and, at this moment, I don't know for sure."
Van Gaal has tested different formations during their matches against Los Angeles Galaxy and Roma during their tour of the United States.