Rooney heads into this afternoon's Premier League duel with Chelsea on the back of successive hat-tricks, part of an eight-goal haul that has shot him into an early lead in the battle to claim this season's Golden Boot prize.
The 25-year-old also scored twice on England duty earlier this month, further evidence he is now completely out of the form dip that lasted nearly 12 months, including a miserable World Cup.
Wayne's world class: Wayne Rooney (centre) is back to his very best form
And Ferguson feels Rooney can now assume wider responsibilities in a youthful United side, which at times averages just 23 years of age.
'He is playing with a zest and energy that has taken him to new heights,' Ferguson told United Review. 'Energy burns in him. But there is also a maturity to his football now that is of tremendous benefit to the team.
'Wayne is ready now to take his career up a further notch and become a leader himself.
'He has already put a marker down on a personal level but now he can assume greater responsibility, and I see his colleagues responding.'
Ferguson is refusing to take anything for granted, despite his side's flying start, which has seen them score a record 18 goals in a 100 per cent start to their first four matches.
The magic number: Rooney has hit back to back Premier League hat-tricks
However, it is form the United manager claims never to have experienced before. And he feels the standard has been set for another productive campaign.
'It is breaking new ground for me, and to say that at this stage of a fairly lengthy career is really something,' he said. 'I am excited. And why not? Because we have been privy to something rather special.
'Of course, you can't help wondering if it is going to last and after a lifetime in the game, football has taught me that there is often a banana skin around the corner.
'But while accepting that our present form is exceptional, I can't help but feel that this season is going to be good for Manchester United.'
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