Obertan: Man Utd followed me for four years
The French winger has only just started playing first team football for United after recovering from a back injury.
He told manutd.com: "I knew United were interested because Jim Ryan (head of youth development) came to watch me play four years ago.
"I knew there was interest there but I didn't expect the move to happen so early in my career. But I felt ready for it, I knew I was ready for the challenge and the change in my life. It was like a new beginning for me and I am just glad to be here and have the opportunity to play for this great club.
"I've always liked English football. When I was in France I would watch English football every weekend. And I think you're right, for my qualities I believe this is the best league in Europe for me. I'm quite fast and I like to attack and be in one v one situations with defenders."