Taking advantage of Southampton's failed attempt to buy the much-sought after youngster, Sir Alex Ferguson pounced and finalised a deal in the same week that Robin van Persie signed on the dotted line.
After passing a medical and signing a five-year contract in M16, Büttner was announced as the club's fourth major signing of the summer with the then-manager describing his new arrival as "one of the best young left-backs in Europe."
Still on cloud nine, he made a dream start by scoring on his first team debut at Old Trafford, dribbling past three defenders to score an unlikely solo goal during a 4-0 hammering of Wigan Athletic.
In total, Büttner made 13 appearances and scored two goals during the title-winning 2012/13 campaign to cap a highly promising start to life at the Theatre of Dreams.
And he hopes there is more to come: "Every game that I play is a bonus. I am still young and I have signed for five years so I have time to come into the first team.