The 20-year-old, part of Brazil's Confederations Cup-winning squad, has been linked with a move to the Premier League during the transfer window.
Tottenham Hotspur have been heavily linked with a swoop for Bernard and reportedly sent scouts to Brazil to watch him in action, while Chelsea have also been credited with an interest.
Porto are among the other clubs believed to be monitoring Bernard's situation and he recently admitted he was considering a switch to the Portuguese champions.
Cuca concedes that it will be difficult to hold on to such a player but says Mineiro would be able to cope as they have a tradition of developing excellent youngsters.
He told UOL: "Atletico Mineiro won't be able to keep Bernard, but this is natural.
"We have to take advantage of having him in Libertadores and if he leaves, as it seems it will happen, it's up to us to develop another player like him."