Germany team manager Olivier Bierhoff is backing Schalke goalkeeper Manuel Neuer to join Manchester United.
Neuer, 25, was Sir Alex Ferguson's top transfer target after van der Sar announced he was hanging up his gloves at the end of this season.
Bierhoff said: "I was a young player when I went to Italy and it was good for me.
"He will fit into the English game. He has to play. He can become one of the best goalkeepers in the world."
Neuer has attracted interest from several top European clubs. His future with Schalke is uncertain with only a year remaining on his current deal.
