Vidic has also recently signed a new four year deal just before Sir Alex replaced Patrice Evra as captain.
A proud moment for the Serbian was captaining the side to victory in the Charity Shield at the start of the new season.
"It is a big achievement for me," he said.
"No-one is going to say they don't want to be the captain of Manchester United and I am very happy with it.
"It is a major responsibility but I have always liked responsibility. I am not a player who shies away from it. Nothing has really changed in that respect."