Once the 29-year-old had made it clear he wanted to leave Arsenal, Juventus was quick to make its interest known.
Premier League champion Manchester City was also in the hunt but
He said: "In these situations, when you have to make a hard decision in your life, I always listen to that little boy inside me. What does he want? That boy was screaming for Manchester United.
"Everyone knows me by now. I love football. I am quite principled in that perspective.
"It is always difficult to find the perfect match but I do feel this is the perfect match for me.
"Manchester United breathes football. If you look at all the players from Manchester United, the stadium and manager, my choice was made very soon."
Australia coach Holger Osieck has put his faith in the old guard to steer the Socceroos to a third consecutive World Cup, despite three key members lacking minutes at club level.