Real Madrid are possibly the weakest team in the semi-finals. Not for their history or name, of course, and certainly not if we analyse the many encounters they've had against Spanish and foreign teams (the latter who have knocked them out only a few times). But this team is very capable of alarming ups and downs.
I start by saying this because it seems that City are seen as a formality but they have sufficient weaponry to bid farewell to Madrid. The English team is well aware that the visitors from the Spanish capital will arrive with an expectation of going through to the final, but everyone agrees that it's the side most suited for City. There are weaknesses in their defence that Agüero or De Bruyne can take advantage of. If the home team can get the ball to these front men, and defend compactly themselves, then Los Blancos could suffer. City are also in a position where they feel they have nothing to lose, as if their Champions League work is already done.