Saying that Real Madrid could pull a surprising win against Manchester City makes Real Madrid the underdog in this match. Real Madrid is a club known for winning big matches in the UEFA Champions League. If Real Madrid beats Manchester City in the quarterfinals of the UEFA Champions League, don't see it as a surprise win but as a deserved one.
The two teams are actually equally strong and if one of them wins it would be very appropriate and that's not only for Real Madrid, because Manchester City will also try not to lose in this match which takes place at Real Madrid's home ground. And even if they lose, Manchester City will try not to lose too much so that they don't have difficulty making a comeback in the second leg when the match takes place at home. So the match will be quite exciting to watch because both of them have extraordinary abilities in the Champions League.