Manchester United boss Sir Alex Ferguson says it will be impossible for him to replace their veteran quartet.

Ferguson knows Edwin van der Sar, Ryan Giggs, Paul Scholes and Gary Neville are all coming to the end of their careers.

He told Inside United: "You can't replace players like that like-for-like. Instead, you look for people who perform in similar positions and who have comparable qualities.

"But you're never going to find replicas - not for those sorts of players. When these men retire we need to look at what's left and what we need to bring in to maintain the right balance. I think we've been good in that respect over the years, and I'm confident we'll get it right again.

"These guys continue to defy age simply because they have the desire to do well and their preparation is so good. Two years ago I was reading that Ryan and Scholesy were playing what would be their last seasons. Then I read the same things last year. Now I think they can still contribute for at least another campaign."