Cameroon's coach Rigobert Song is expecting an "absolute scorcher" of a game against Brazil on Friday, a match he believes his victory-starved side is capable of winning having beaten the five-times World Cup winners before.
Winless at the World Cup since 2002, Cameroon are tied with Serbia on one point from their opening two matches and need to beat already-qualified Brazil in Lusail to stand a chance of reaching the last 16.
Brazil will field a different lineup against the African side, with the possibility of a game on Monday if they finish top of Group G.
"Cameroon have beaten Brazil before, yes. So it's not completely out there," Song said.
"Obviously, this Brazilian team will be beautiful to me. I have so much respect for Brazil, but in football there are realities that are slightly different," Song said.
"Sometimes there is an upset, anything is possible. And that is why I am firmly convinced that we are capable.
"Tomorrow will be a game that will be an absolute scorcher ... We've already beaten them and we can beat them again."
It will be a tall order, with Cameroon having not reached the last 16 in more than three decades.
The African side lost all their group games in 2010 and 2014 and have been beaten twice by Brazil at the World Cup.
Cameroon's sole competitive win over Brazil was at the Confederations Cup in 2003 in France.
Song said he still believed a "beautiful victory" was possible.
"We know that it will be no walk in the park for us tomorrow. But it will be a highly exciting game," he said.
"We're ready for the fight. We're ready to give everything we've got."