Arsenal star is feeling young at heart
He admits his return to Old Trafford will be emotional.
"It is going to be weird going into the visitors' changing room, to see the supporters and all the people who work at the club again," Silvestre told L'Equipe.
"It is going to be moving. Nine years at one club, it's a long time, it is a part of my life. And it isn't any old club, it is a legendary club.
"I could have stayed for my 10th year and had my testimonial. It surprised everyone (that he moved) but I wanted a new challenge.
"Ferguson did me a favour, he had never done it before," added the Frenchman.
