Clubs from Brazil actually make big surprise and great impression in this Club World Cup tournament. Inter Milan truly have had a very long seasons with many matches that are overwhelming for their players. Likely some of Inter Milan have been exhausted and they hope that this Club World Cup does not exist.
This big issue of Inter Milan gives Fluminese very good opportunity to beat this giant from Italy. With talents of Brazilian players, Fluminese can play this match ambitiously and try to beat Inter Milan. They know that beating Inter Milan down is very easily and they don't have to feel fearful about this opponent.
Fluminese made a big surprise by beating the Champions League finalists... maybe you are right the Inter players are starting to get tired because they seem to have no passion at all to play.
Fluminese now beat Inter Milan 2-0 even though Inter Milan often made attacks several times but it did not result in goals... many good chances but in the end many shots went wide as if none of the shots were experienced... Damn honestly I'm disappointed Inter Milan lost.