At last, it is official.
The move sees Mkhitaryan going in the other direction towards Arsenal, not that United wanted to get too hung up on that.
"I am thrilled to be joining the biggest club in the world".
'Since I was a young lad I've always said my dream was to play for Manchester United, and I'm not just saying that because I'm here now and it's come true, ' he said.
Arsenal boss Arsene Wenger said he was happy to acquire Mkhitaryan.
The Armenia global is set to move to the Emirates in a straight swap with Alexis Sanchez and will earn slightly more than the £200,000 per week he gets at Old Trafford - plus the remainder of his United deal will be paid off.
However, Sanchez also made a point of reacting to those ex-players who had questioned his attitude during the final stages of his career at Arsenal.
GETTY Manchester United star Alexis Sanchez has won two FA Cups with Arsenal
Despite City reviving their interest in January, and Chelsea inquiring about a deal, the 29-year-old opted to join Jose Mourinho in the red half of Manchester.
But, Manchester United have swooped in under the radar and exploited Sanchez's desperation to leave Arsenal by blowing City's offer out of the water, while also meeting Arsenal's needs in the shape of a rare swap deal involving Henrikh Mkhitaryan.
As is the case with most footballers these days, Sanchez left a post for Arsenal fans on Instagram, but it was met with mixed emotions as some vilified him while others understood his ambitions of moving to a more competitive club.
Sanchez has scored seven Premier League goals and eight in all competitions for Arsenal this season and finished with 24 goals in the league, and 30 overall in 2016-17.
Henrikh Mkhitaryan has been tipped to play a key role in 2017/18, beginning tonight in Macedonia.
While his strike rate in the league over 3-1/2 seasons at Arsenal is nearly one in two, his statistics this term are less impressive.
"Now that I'm here, I'll do my best for this club to create history", he said.
Now, he'll be earning a reported weekly wage of 400,000 pounds ($560,000) - possibly making him the highest-paid player in the Premier League - at what he perceives to be "the biggest club in the world".