United announced on Monday evening that they had signed Sanchez from Arsenal in a swap deal with midfielder Henrikh Mkhitaryan.
Sanchez has signed a four-and-a-half year deal with the club, while Arsenal announced that Mkhitaryan had joined the club “on a long-term deal”.
In his first interview as a Manchester United player, Sanchez said he was “thrilled” to move to Old Trafford and spoke of his delight at linking up with Mourinho.
“I am thrilled to be joining the biggest club in the world,” he told the club’s official website.
“I have spent three-and-a-half wonderful years at Arsenal and I bring with me very positive memories of that great club and its fans.
“The chance to play in this historic stadium and to work with Jose Mourinho was something I could not turn down.
“I am very proud to be the first Chilean player ever to play for United’s first team and I hope I can show our fans all around the world why the club wanted to bring me here.”
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