Chile coach Jorge Sampaoli temporarily suspended a practice session when a Brazilian news helicopter flew over the team's base Thursday, two days before the countries meet in the second round of the World Cup.
The team's communications director, Hector Olave, said he asked Globo not to broadcast any of the images so Chile's tactics wouldn't be revealed. Olave said the private broadcaster later apologized for the incident at the Toca da Raposa II facility in Belo Horizonte.
Olave said Sampaoli was worried "because he was working on tactics and he didn't want them to know how he plans to approach the match" against Brazil at Mineirao Stadium.
The players reacted in jest, saying they aimed shots at the chopper.
"We tried to hit it with the ball, but we couldn't," defender Mauricio Isla said.
Former Brazil striker Ronaldo said Chile is the team that should be worried about Saturday's match, saying "they are infinitely more concerned than we Brazilians."
Not everybody agrees.
After the World Cup draw more than six months ago, Brazil coach Luiz Felipe Scolari said his biggest concern was facing Chile — that's when the more likely alternatives were Spain or the Netherlands. At the time, Scolari said he hoped Chile "wouldn't qualify" for the second round.
After finishing second in Group B behind the Netherlands, the Chilean players are focused on how to knock the hosts out of the tournament.
"We came to make history," forward Alexis Sanchez said. "We beat the world champion (Spain). We tripped up against the Netherlands, but we saw the errors we made.
"We gave them opportunities and they took advantage of them. That's the error we won't make against Brazil."
Sanchez said the team is drawing inspiration from the attitude and work ethic of players like Gary Medel and Arturo Vidal, praising their graft at the back and in midfield.
"Chileans sometimes don't have this winning mentality," he said. "We need to have this mentality, believe in what we're doing."
Chile's 2-0 victory over Spain in the group stage was an important step, he said.
"Not all of us can be friends, but on the pitch we support each other," he said. "We have to play with heart."