Olympic football review:Ten-man Senegal blew Group A wide open with a shock 2-0 win over highly-fancied Uruguay at Wembley. Impressive teenager Moussa Konate scored twice, either side of Abdoulaye Ba's first-half dismissal for hacking down Luis Suarez.
In a match littered with fouls - and five more yellow cards - Senegal kept the World Cup semi-finalists at arms' length, Suarez coming closest when he headed into the side netting.
Outsiders to qualify before the competition started, Senegal know a victory against United Arab Emirates in Coventry on Wednesday will send them through, leaving Great Britain and Uruguay to scrap it out for the additional quarter-final berth.
Neymar underlined his status as one of the hottest prospects in world football by scoring a breathtaking free-kick as Brazilbeat Belarus3-1 at Old Trafford.
This week Barcelona made it clear they want Neymar to join them after the Olympics and it is easy to see why. His dazzling skills wowed all 66,212 spectators throughout this Group C match, with the crowning glory coming in the 65th minute when the 20-year-old bent a peach of a set-piece over the wall and past the sprawling Aleksandr Gutor.
Brazil have now qualified for the last eight with one match to spare, but they were given a stern test by Belarus, who opened the scoring through Renan Bardini Bressan.
Neymar crossed for Alexandre Pato to equalise and also set up Oscar for Brazil's third after his brilliant effort had put them ahead.
Tottenham playmaker Giovani dos Santos was Mexico's hero with both goals in their Group B 2-0 victory over Gabonat the City of Coventry Stadium.
Giovani, who struggled to earn a place under Harry Redknapp at White Hart Lane, was introduced as a second-half substitute and broke the deadlock after 63 minutes.
He then scored from the penalty spot in injury-time after Gabon defender Henri Ndong was sent off for a professional foul.
The former Barcelona player, signed for Tottenham by Juande Ramos four years ago, secured Mexico their first win of the tournament and put them on course for the quarter-finals.
Kim Bo-kyung was South Korea'shero with a second-half winner as they beat Switzerland2-1 in their Group B encounter at the City of Coventry Stadium.
Kim, who recently moved from Cerezo Osaka to Championship club Cardiff, volleyed home a deflected cross to move Korea level on four points with group leaders Mexico.
Arsenal's Park Chu-young had opened the scoring for Korea but Switzerland replied instantly through Innocent Emeghara only for Kim to settle the issue.
Egypt'shopes of qualifying for the last eight took a blow as they drew 1-1 with New Zealandat Old Trafford after wasting several chances.
Egypt fell behind to a 16th minute strike from West Brom's Chris Wood, but Mohamed Salah equalised from close-range at the end of the first half.
The Africans could have had at least seven goals by the final whistle but a mixture of last-ditch Kiwi defending, and some awful finishing from Egypt, meant they had to settle for a draw in what was a poor-quality contest.
Should Brazil beat Belarus in Manchester on Sunday afternoon, Egypt will have to beat the Europeans on Wednesday to qualify for the quarter-finals, while minnows New Zealand will have to beat the South American side to progress from Group C.
Striker Kensuke Nagai fired Japan to the brink of the Olympic quarter-finals with the late winner in a 1-0 victory against Morocco.
The Grampus Eight frontman struck with an instinctive lob six minutes from time to settle a tight Group D encounter.
