I've said it before & I'll say it again....
Modern team formations usually include one to three strikers; two is most common. Coaches typically field one striker who plays over the shoulder of the last defender (close to the opposing team's goal), and another attacking forward who plays somewhat deeper and assists in making goals as well as scoring.
The former is usually a large striker/centre-forward, typically known as a target man, who is used to win long balls or receive passes and "hold up" the ball as team-mates advance and they are also normally the principal goal-scorer of a football team. Centre forwards act predominantly as "targets" or the focal point of an attack; it is the duty of the midfield to supply and to assist them to score.
The latter is usually a deep-lying forward/ supporting striker, typically known as a playmaker or Number 10. Because of their great technical ability, accurate passing skills and impressive vision, they have also been positioned as a playmaker in the central slot behind the forwards. In any zone surrounding the penalty area, their prowess as a creator of goals came to the fore. Simply put, they are the orchestrator of thier team's offensive play & they provide the link between attack & midfield.
From there, I think ue can clearly tell which position does Rooney excels in & is terrible at. He relies on his great ability, superb technique, sheer brilliance, explosive bursts of thunderous pace & golden touch to score a goal. Not requiring excellent aerial prowess & clinical finishing ability. Those are what he lacks in the first place. Atm, Fergie's stationing him as a centre-forward/ target man, something which he doesn't excel yet performs terribly at. Go on SAF, put Rooney where he is originally & leave him there for good. That is, a playmaker!
