The Scottish boss has been reflecting on the former Everton star's career as today marks the 10th anniversary of Rooney's first ever Premier League goal, which came against Arsenal when he was 16 years old.
"We knew what we had at the club," Sky Sports News quotes Moyes as saying. "I got told about him as soon as I came in the door.
"He was everything we hoped. He was a man when he was very young. He had the ability and the talent but also a desire to play football.
"Wayne could have been a goalie, he could have been a right-back, a centre-half, he could play any position because it was his love for football which I think was one of the biggest factors."
Rooney moved from Goodison Park to Old Trafford in 2004.