Ronaldo ran riot in the Bernabeu in September, dramatically robbing Mancini’s men of a point in injury time.
The former Manchester United hero returns to Manchester tonight hoping to sentence United’s bitter rivals to an early Champions League exit.
And Mancini believes Ron would deserve to be hailed as the best player on the planet if he scoops the Ballon D’Or next month.
The City boss smiled: “How do we stop him? Maybe we’ll call the police.
“He’s a top player and, when you come up against someone who can score one or two goals every game, it is difficult.
“We will need to concentrate.
“For me Ronaldo deserves to win the Ballon D’Or. He scored so many goals last year and that helped Madrid finish above Barcelona.
“But I hope he can have a bad night on Wednesday. Maybe they can leave him at home.”