In general, yes, they are all pros (and I’m not just talking about City players) and essentially for them the whole season is an endless series of games and they are all important and in the end everything merges into one endless match. Therefore, in virtually every game everyone shows their average level. But the game with Real Madrid, especially in the quarterfinals of the Champions League, is very different from all other games, so I think that no matter how hard Guardiola tries, the players will think about this game not only when necessary (immediately before the game) but also long before it.
It is always hard to maintain normal focus before an important match in Champions League. It is where all players want to win and lift the trophy so no matter what their coach says, players will be distracted a lot to Champions League than their domestic league, Premier League.
This season, Manchester City are defending their title in Champions League and their players only won one title last season so I believe their ambition to win it again, is still big. They know that they will make history as a second club can defend title in Champions League after Real Madrid. It's nothing better than moving nearer to the final match, by beating Real Madrid, the only champion so far successfully defend their trophy.