The much-vaunted Brazilians, who suffered a shock defeat by Japan in their opening match, produced some flair at last. They were joined in the last eight by Ghana, Mexico and Nigeria, who qualified despite the defeat.
The Barcelona-bound PSV Eindhoven striker Ronaldinho, 19, whose craft and guile belied his tender age, scored the only goal for Brazil midway through the first half. He shrugged off some tough defensive attention before slotting the ball neatly between the diving goalkeeper and the upright.
The win for Brazil, which also gave them top place in the group above Nigeria on goals scored, means they now meet another African team, Ghana, in the next round.
Ghana's 1-1 draw with Mexico in Washington DC was enough for both teams to edge out South Korea, who had gone into the final round of group matches in top place in Group C.
The Koreans were beaten 2-1 by Italy in Birmingham, Alabama - a result which came too late to rescue a disappointing tournament for the Italians. Two goals from Marco Branca, the winner scored eight minutes from time, left South Korea tied with Ghana on points and goal difference - but the Asians went out after scoring fewer goals.
Japan scored two dramatic injury-time goals to overhaul Hungary 3-2 in Orlando, but they were eliminated on goal difference. Mexico, roared on by a passionate crowd in the American capital, had a goalkeeping error by Ghana's Simon Addo, who misjudged a harmless cross that led to a late Mexican equaliser, to thank for their progress.
MEN'S TOURNAMENT Quarter-finals: Today (Miami): France v Portugal; (Birmingham, Ala): Argentina v Spain. Tomorrow (Birmingham, Ala): Mexico v Nigeria; (Miami): Brazil v Ghana.Reuse content