Neymar's superb two-goal show inspired Brazil as the hosts eased through to the last 16 of the World Cup, finishing top of Group A to set up a meeting with Chile.
Neymar scored two first-half goals as Cameroon were put to the sword in Brasilia, going down 4-1 in their third defeat in three group games.
Neymar is still only 22 and already has 35 goals in 52 caps to his name. Only Pele and Zico have a better goals-per-game average for Brazil, and both those greats' totals of 77 and 66 respectively look achievable for this prodigy.
His two goals put Brazil on their way and though Joel Matip's first-time finish initially put Cameroon level, Fred and substitute Fernandinho put a gloss on the scoreline.
Given Cameroon's dismal showing at this tournament there was little expectation that this would be anything other than a Brazil win, and so it proved as the hosts dominated from start to finish.
Fred, who had had a wretched first two matches himself, somehow contrived to miss a great opportunity after good work from Hulk, allowing Matip to block.
Cameroon did then enjoy a period of good possession but it all went wrong shortly after Allan Nyom was lucky to escape punishment for a cynical push on Neymar near some advertising hoardings.
Hulk may have been on the field, but it was Neymar that Cameroon didn't want to make angry, and with a minute he had shown them why. Luiz Gustavo took out two defenders with a curving ball from the left and Neymar just guided it into the net with Cameroon keeper Charles Itandje rooted to the spot.
Neymar then had a 20-yard strike parried before Cameroon managed to expose Brazil's fragility at the back.
From a corner Brazil's skipper Thiago Silva nearly headed the ball into his own net but it thumped back off the angle. From the follow-up however Nyom beat Dani Alves twice and crossed low to leave Schalke defender Matip with a simple finish.
The silence that greeted that goal engulfed the whole country but they were not quiet for long. Hulk, whose World Cup has also yet to get going, had a low shot saved before Neymar once again proved unstoppable.
This time he ran at the Cameroon defence and from 20 yards out fired through the legs of Nicolas N'Koulou. Keeper Itandje, showing again just why Liverpool let him go, dived the wrong way after being wrong-footed and Brazil were back in front.
The best move of the half involving Neymar and Fred then ended with Hulk scooping over under pressure.
It was more of the same in the second half, Fred producing an outstanding strike with the outside of his foot that Itandje this time managed to get a hand to. Neymar then went for goal from a free-kick from an absurdly tight angle only for Itandje to turn it over.
It was only a matter of time before Brazil broke through again, and Fred - heavily criticised for his performances in this tournament by Alan Shearer in the build-up - made it 3-1. It had more than a suspicion of offside when David Luiz curled over a cross but the officials did not spot it and Fred could barely miss with the header.
Marcelo then tried his luck with a fierce strike that was blocked before another intricate move saw some delightful one-touch play between Fred and Oscar set up Fernandinho. The Manchester City midfielder stretched to poke home and spark another round of joyous celebrations around the country.