Marouane Fellaini is supremely confident that he will vindicate his £27.5million price tag.
But Fellaini has faith in his ability and has tried to assure Red Devils supporters that he is the player the club has been searching for.
"I'm very, very happy. It's a big moment for me. I waited for a long time, I've worked hard for this and I'm very happy to join this big club, this great club. I hope to do everything for this club," he said.
"It's the biggest club in the world so of course I wanted to join this club. I tried everything to join the club. It's been difficult, a very long day. I waited to the end. I know the situation, but this day has been very long.
"It [Old Trafford] is a big stadium, a big club. I hope I can score a lot of goals for Manchester United.
"When I was young it was a dream to play for Manchester United. Now I'm here so I'll try to give my best to the club. I want to win trophies. That's the most important thing."