He said: “I was not thinking of signing Matic because I never go for players who I think are an impossible mission to sign. I felt that there would be no chance.
“So when I got the call that Matic wants to play for me and wants to play for Manchester United - and that we could make it happen - I thought he's the perfect player for me.
“When I joined United last year I thought immediately that we needed a Matic. There aren't many like him. Just a couple. He is one of those players who has no question marks over him.
“He won't need time to adapt. He isn't a young guy who comes from another country or needs to learn the Premier League.
“Only last week he was 29, with five years in the Premier League and lots of experience. And he is one of those players who gives me what I like: consistency. I can trust that he will perform.
"He is a fantastic signing."