De Gea is expected to leave the club in the coming weeks as Real Madrid want to tie up a deal for him before their pre-season tour in July.
His imminent departure means United are looking to find a replacement for the goalkeeper they have transformed into one of the best in the world.
Yet, despite talk of Jasper Cillessen coming to United, Van der Sar feels United may already have the perfect replacement for De Gea in Valdes.
“It depends whether they are looking for someone with reaction saves or someone who is commanding and a more outfield type of player.
“If your team plays further away from goal and you have a goalkeeper who likes to protect his six-yard box, then the match will not be there. Barcelona played a lot away from goal and that is something Van Gaal finds important. Valdes has a lot of experience and a great pedigree.”
In terms of being a good judge of a good replacement, Van der Sar is as good as any to do so.
Valdes arrived at United in January on a free transfer after almost a year out with a ligament injury. Since returning, he has recovered well and played in the last two games of the season for United as De Gea picked up an injury himself.
Louis van Gaal made a big effort to help Valdes recover from his injury problems and that may well have been because he saw him as the perfect replacement for De Gea.