Internacional striker Leandro Damiao inspired 10-man Brazil to comfortable 3-0 Group C victory over New Zealand to send them into the quarterfinals with a 100 per cent record.
The 23-year-old set up midfielder Danilo to open the scoring and then claimed his second of the tournament before the break, with Tottenham's Sandro adding a third in the second half to cement the win which will see his side return to St James' Park on Saturday evening.
Pre-tournament favorites Spain embarrassingly bowed out of the men's Olympic football competition without a goal to their name.
A month ago their compatriots retained their European Championship crown to add to World Cup glory, but this has been a few days to forget for coach Luis Milla's side.
The goalless draw with Morocco, in front of a crowd of 35,973 at Manchester United's Old Trafford, also ended the faint hopes of the north Africans, leaving Japan and Honduras as the surprise qualifiers from Group D.
Oribe Peralta's second-half strike saw Mexico top Group B with a 1-0 victory over Switzerland at the Millennium Stadium.
The Swiss needed a win to have any hope of reaching the Olympic quarter-finals, and they enjoyed the better of the opening half with Innocent Emeghara and Admir Mehmedi missing presentable chances.
But the failure to take their chances was punished by an improved Mexico after the break, with Peralta's low finish setting up a last-eight meeting with the runner-up in Group A.
Egypt qualified for the quarterfinals of the Olympics from Group C with a deserved 3-1 win over Belarus at Hampden Park.
The North Africans got the all-important breakthrough 11 minutes after the break as Mohamed Salah sweetly controlled a long ball through the middle and slotted home his third goal of the competition.
Belarus were then undone by two flowing moves from the Egyptians allowed Marwan Mohsen and then Mohamed Aboutrika the easiest of finishes.
Andrei Voronkov pulled one back with a fine header three minutes from time but it was too little too late for Belarus, who bow out of their first ever Olympics at the group stages.
They will meet Japan in the last-eight, who qualified with Honduras after fighting out a goalless draw at the City of Coventry Stadium.
Japan finished top of the group with seven points from three games and they will take on Egypt in the last eight.
Runners-up Honduras will face a more daunting test against one of the tournament favorites in Brazil.
South Korea set up a quarterfinal meeting with Great Britain despite being held to a disappointing 0-0 draw against Gabon at Wembley.
Arsenal's Park Chu-young and Sunderland striker Ji Dong-won were both guilty of missing easy chances and the quality of the Asian side's finishing - and their play in general - was very poor.
Gabon came the closest to clinching victory in the second half when Levy Madinda hit a post, but the draw was enough to see Korea through to the last eight after Mexico beat Switzerland at St James' Park.
