just imagine what if you had 2 teams that you really like? would you like both of them to become UCL title holders? 
but I'm sure you will prefer Man City to be the UCL title holders this season.
IMHO, each person must be a fan of 1 football team. I don't know if someone can be a fan of 2 teams or more. but I'm sure you will prefer Man City to be the UCL title holders this season.
Sure, there will be 1 winner only, you must choose 1 team to be the favorite team. I prefer Man City to win it because their squad looks better, specifically when all the players are in good condition. Now, the injury players have recovered, they are ready to show their best performance in UCL.
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Strange reasoning. It’s just as strange as arguing that you can’t be a fan of barbecue and computer games at the same time. In addition, I am generally against being a real fan of any club - sport is entertainment/business, but not a religious faith (and the wars that result from this). I like several clubs and over the course of the seasons my preferences change, I don’t see anything illogical in this: if a club provides a good product (game) I like it, if not, then I will find a better product.