The Chilean has left Arsenal for Old Trafford, with the former Borussia Dortmund star heading to the Emirates as part of the deal. Manchester United have completed the transfer of Alexis Sanchez from Arsenal, with Henrikh Mkhitaryan joining the Gunners in a straight player swap with no fees involved.
“I am thrilled to be joining the biggest club in the world," Sanchez, who takes the club's No.7 shirt, told Man Utd'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.
Meanwhile, Mkhitaryan's exit as part of the deal ends the Armenian's 18-month spell at rollercoaster Old Trafford since arriving from Borussia Dortmund in the summer of 2016, with the 29-year-old signing with the Gunners until the summer of 2021.
He spent two lengthy periods out of favour under Mourinho but did play a huge part in United's Europa League triumph in 2016-17, scoring the second goal in the 2-0 victory over Ajax in last May's final.