The 25-year-old was unveiled at a media conference at United’s Carrington training ground on Monday following his club-record £37.1m switch from Chelsea.
He’s one of the best players in the history of this country
Mata is expected to line-up as part of United’s potentially lethal quartet of Adnan Januzaj, England international Rooney and last season’s top goal-scorer Robin van Persie.
And the Spain international is particularly looking forward to teaming up with one of England’s best-ever players in the shape of Rooney.
“For me he’s one of the best players in the history of this country. He’s an unbelievable player,” Mata said.
He added: “He’s a striker who can score, assist and come into midfield to take the ball.
“I will try to connect with him as much as possible and find the gaps in rival defences. I think that’s my best style of play, to get into positions where I can assist the strikers.”
Mata scored 20 goals and made 35 assists as Chelsea finished in fourth place and won the Europa League crown last season.
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