His teammates at United have already praised the midfielder and wished him well at Arsenal.
Speaking to MUTV, Sanchez added: "Since I was a young lad I've always said that my dream was to play for Manchester United, and I'm not just saying that because I'm here now and today it's come true. Now I'm here, I'll do my best for this club to create history". "I must say he's a player who has all the attributes".
Armenia worldwide winger Mkhitaryan, also 29, fell out of favour with United manager Mourinho after just 18 months at Old Trafford.
The never-ending saga of Chilean global Alexis Sanchez has officially come to an end with the wantaway winger has penned a four-and-a-half-year deal with Jose Mourinho's Manchester United from Arsene Wenger's Arsenal.
Sanchez has scored 80 times for Arsenal since joining from Barcelona for £30m in July 2014, and was last season's top scorer with 30 goals in all competitions.
MANCHESTER UNITED Alexis Sanchez signed for Man Utd yesterday
Arsène Wenger said: "Henrikh is a very complete player".
Should Manchester United manager Jose Mourinho opt to stick with his current formation following the signing of Sanchez, one of Marcus Rashford or Anthony Martial looks set to suffer.
"He will bring his ambition, drive and personality, qualities that make a Manchester United player and a player that makes the team stronger and the supporters proud of their club dimension and prestige". "He is a player that we will not forget, especially for his contribution to our Europa League victory".
The Sanchez-Mkhitaryan deal is the latest move of a January transfer window during which Liverpool sold Philippe Coutinho to Barcelona for 160 million euros and signed central defender Virgil Van Dijk from Southampton for £75 million (85.5 million euros).
Recently Arsenal has been also chasing Henrikh's former Borussia Dortmund team mate Pierre-Emerick Aubameyang, and reports are beginning to emerge that the Gunners have agreed personal terms with the striker but no fee has been finalized as yet.
Alexis Sanchez will hope to hit all the right notes at Manchester United after his move to Old Trafford was officially announced with a musical twist.More news: Early Arrival Would Have Made a Lot of Difference, Says Shastri
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