Rooney netted twice in Manchester United's 3-2 first leg win at the San Siro and will play tonight after recovering from a knee injury.
Milan ace Ronaldinho told The Sun: "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.
"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."