I'm just wondering how important for big clubs these state championships it?
Not very much. As mockery, there are some people who say it's just a consolation prize for clubs which can't win more important championships like Campeonato Brasileiro and Libertadores da América. It's always nice to win a new trophy and title, but truth is that big clubs fight for the big achievements and will feel proud of themselves only if they manage doing so.For some clubs it serves as preparation for the season, with coaches testing tactical schemes and giving opportunities to players from the youth divisions, while for other smaller clubs it is very important because the state championships are qualifying championships for a place in the Brazilian Cup, that is, the only opportunity for many teams to compete in a national level championship.
Another difference is the rival clubs that always decide among themselves who is the best in the state, like, Flamengo x Vasco, Palmeiras x Corinthians, Internacional x Grêmio...
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