Ruddock was at the Hammers when Ferdinand was coming through the club's youth system.
"Yeah, you could see it even then. You can see a good player, but Rio Ferdinand could play in any position on the pitch, even at international level. He can play along the back four, along the midfield but I won't say up front because he is one of the worst finishers I've ever seen in my life! He's scored a few, but he can't beat me on goal scoring," he told manutd.com.
"He was brilliant. When the lads were 15 or 16, Harry used to let them train with the first team because he knew them, so we had the likes of Rio, Michael Carrick and Joey Cole. They were around the first team dressing room, so when they came into team they were already one of the chaps and one of the lads, so it wasn't a hard transformation for them."
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