He insists the Premier League remains United's No.1 target but dismissed suggestions Sir Alex Ferguson's side thought they had a divine right to be champions after a hat-trick of title wins.
"No, no, it's not for you to keep," Van der Sar told the Daily Mail. "You have to work hard for it during all season. And that's what we are doing now, working hard.
"I think you want to get the Premier League title back, that's for sure. That's the priority. We narrowly missed out last year although we had loads of injuries and lost too many games. 'Hopefully when the big boys are coming back at the beginning of August, the middle of August, we should be ready for a new challenge."