"It is a very contemporary ceremony. Even without special effects it talks to people about the future. In a very humble way. It is not a display of how good or modern Brazil is."

Opening ceremonies are among the best-kept secrets of the Games along with the final torchbearer who will light the cauldron.

That cauldron, however, will not be like past big structures with huge flames, visible for miles.

"It will be a low-emission cauldron as it would be an oxymoron to talk about sustainability and then burn massive amounts of gas," Balich said.

"It is a small burner with a kinetic sculpture."

While the real flame will only be accessible for Olympic stadium ticket holders, a smaller copy will be placed in a live site in central Rio for fans to take photos of.

Some 4,800 people will take part in the opening ceremony along with about 11,000 athletes, who will enter the stadium and, due to the lack of a track, will gather at the centre of the legendary football arena.

"The ceremony has a purpose," Balich said. "Talking in a positive way in terms of sustainability. Doing a dry celebration is not enough. The fact that we are taking position might not make everyone happy but that's what it is."