Mexico stunned Brazil in the 2012 Olympic final, winning 2-1 thanks to a brace from Oribe Peralta - and Silva, who also skippered his country in London, is well aware of the Central American nation's quality.
Brazil take on Mexico in Fortaleza on Tuesday, with both sides knowing that a win would put them firmly in control of Group A at the FIFA World Cup.
And while the hosts will be overwhelming favourites to follow up their 3-1 win over Croatia last week with another victory, Paris Saint-Germain centre-back Silva is wary of Mexico's attacking threat after Peralta and Giovani dos Santos looked in good form in their 1-0 success over Cameroon.
"They are players of great quality," said Silva.
"I've already played against them several times, especially at the Olympics. Unfortunately we lost in the final but we're calm because we know we have a great cast, a great coach and mainly because we are living in one of our best moments.
"So I can say that we are calm but that doesn't mean we aren't aware. Quite the opposite. As quality players we have to be alert at all times.
"Mainly because Giovani and Peralta, they can decide games in a matter of seconds. So to not be surprised, we are studying their offensive action."
Brazil could be without Hulk, who limped out of training on Sunday, against Mexico due to the striker's ongoing struggles with a leg muscle problem.
Coach Luiz Felipe Scolari appeared confident the Zenit forward will be able to feature, but added that the likes of Willian, Bernard and Jo are capable of deputising if needs be.
"I do lose if there is a difficulty with Hulk. In the system that we have been playing for a long time he has been playing well," Scolari said.
"He has been positioning himself in the way that can play in both the right and the left.
"The other players have slightly different characteristics and have different qualities to Hulk that can add to the team, speed, stronger marking, or ability to position themselves that can help us over there in the game against Mexico.
"So as Thiago said I have 23. In my opinion, all of them I think were well chosen and there will not be any problems if by chance the Hulk cannot play."
