"They tried to sign him this season," Metzelder said of United and Raul. "He talked about it to me. I don't know if he thought about it.
"A player like him has offers - from clubs in the United States, England but also Schalke. I tried to convince him.
"He got to know Germany in the 2006 World Cup and knows the atmosphere, the stadiums, the infrastructure.
"I said to him, 'You have to experience it'. He's a big player and his influence is great."