While the German giants got through the group stage as runners-up behind Benfica, their Brazilian rivals finished ahead of Chelsea in their group.
It’s also likely that Flamengo will have bigger numbers in the stands, given the large South American diaspora in Miami.
But Stanisic is confident in Bayern being favourites to win the tie, even with the notion that South American teams have an edge.
"I don't think South American teams have the edge because we've been working since the start of the season last year. This match is going to be an even one, and it will come down to who wants it more," said the 25-year-old.
Bayern beat Auckland City 10-0 in their opening game, then got a hard fought 2-1 win over Boca Juniors before losing 1-0 to Bayern Munich.
However, Stanisic insists that they are getting better with each game and they are coping with the hot weather.
"Every game for us is a vital game. Here in America, every game has taken place in a different environment, and we've adapted rather well to the hot conditions."
Flamengo are also highly confident as the tournament heats up, but Stanisic says they will cope with whatever is thrown at them.
After playing Boca Juniors in the group phase, Stanisic spoke about the lessons learnt from facing a South American outfit.
"What we learned as a team is that we should never give up, and we should play until the last second. We must remain patient and not allow ourselves to be roped into the South American way of playing."