The defender was still at Everton when Rooney was breaking through.
Unsworth told the Sunday Telegraph: "I will never forget Wayne's first session. He came in as a 15-year-old, training with the seniors, and it was a 'wow' moment. 'Cocky' is the wrong word, but there was an aura about him then.
"I saw his desire. He knew he could compete at this level. He had everything: he could compete physically, run, got a trick, clever, can finish.
"Wayne's a nice guy as well. People don't see that side. I know he's had his issues. I've been to United a couple of times to watch training. Wayne was straight over to say 'hello', have a chat, nothing 'big time'.
"I'm an Everton fan - so is Wayne. Once a Blue always a Blue - he made that famous didn't he? He might end up back there at the end of his career."
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