The Group A rivals meet in Fortaleza on Tuesday having each made winning starts to their respective campaigns.
Brazil saw off Croatia 3-1 in the opening game of the tournament before Mexico edged past Cameroon, and a further victory for either side would likely all but confirm their place in the knockout stages.
Marquez, appearing as skipper at his fourth World Cup finals, feels his Mexico team-mates should capitalise on the opportunity to spring a surprise against Brazil.
"We have to make the most of this opportunity - it is a showcase for all of us, for many of them it is an opportunity to go up one more level," he told Globo.
"This is something that rarely happens."
Former Monaco and Barcelona man Marquez has picked out the attacking trio of Neymar, Oscar and Hulk as players Mexico will need to keep a close eye on.
Marquez, who now plies his trade with Leon, says his team will be required to close down the space and deny Brazil opportunities if they are to take anything from the game.
"We have to cover, have two against one, be fast and reduce the spaces on the pitch - do not let (Neymar) play," he added.
"It was a good win (against Cameroon), and very important. Against Brazil, it will surely be a very difficult game. We know the talent of Neymar, Oscar, Hulk but we will train in ways to handle them."
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