The 19-year-old trickster, who is in Brazil's Olympics squad, has been tipped to move to Old Trafford for several weeks, but the boss batted back Sunday night's reports that the move was tied up.
"It's not correct," the United manager told a press conference in Shanghai. "We haven't reached an agreement for the player. We've shown an interest but until such time a we get a deal agreed we can't say he's our player."
Sir Alex confirmed that the club are exploring a variety of options, with a view to bringing in more than one player before the start of the 2012/13 season proper.
"We've signed two players in the summer: Kagawa and Powell," he said. "We think they both have fantastic potential.
"At this moment we're looking at other options in terms of bringing other players in. We're not lying on our backsides doing nothing. We're trying hard to bring other players to the club."