Manchester United confirm Mauricio Pochettino has joined as head coach on a contract until June 2029.
Cost for Pochettino ($10m) and his staff ($2m) is $12m.
Long-standing assistant Jesus Perez has also joined. Perez has hoped for a move to Old Trafford for some time.
Pochettino is viewed by Manchester United as an experienced coach with a philosophy and personality well-suited to the role.
His proven track record of building a strong culture stood out.
Manchester United sources say the decision to hire Pochettino was unanimous. The Glazers played an active part in the process.
Pochettino was the only coach the club spoke to directly. Eddie Howe did not have a formal interview.
Pochettino will be in charge for Liverpool on November 22. US Soccer say he will remain in charge for both Nations League games against Haiti first.