Rooney was superb during the first leg of the last-16 tie in Milan, scoring twice as United earned a 3-2 advantage to protect at Old Trafford.
But Brazil legend Ronaldinho is not expecting a repeat performance from the England star who has 28 goals in all competitions this season.
Double trouble: Rooney stunned the Italians with two goals in the San Siro
'Rooney was incredible in the first match. We have watched videos of the game and the key to victory for us will be stopping him receiving the ball close to our penalty area,' he said.
'If we can stop him our own options soar. We can beat United. As far as I am concerned, this match is like the Champions League final itself.
'I see a very attacking game with many goals.'
Rooney is on course to match Cristiano Ronaldo's 42-goal haul of two seasons ago.
And the Real Madrid forward said: 'He is sensational at the moment. If he carries on like this he will soon be very close to the number of goals I scored.'
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