Rio De Janeiro, Aug 5: Barcelona star Neymar failed to provide the flying start Brazil wanted in their quest for a maiden football gold medal as the hosts were held 0-0 by 10-man South Africa in their Olympic opener.
Neymar is by far the biggest name taking part in the football competition and has been tasked with restoring pride to Brazilian football after a catastrophic 7-1 defeat to Germany on home soil at the 2014 World Cup.
However, he endured a frustrating afternoon on a sandy and slow surface in Brasilia as South Africa held out despite Mothobi Mvala's red card half an hour from time.
Group A is now in a four-way tie on one point after Iraq and Denmark also played out a scoreless draw earlier. In contrast to the swaths of empty stands across the six cities being used to host the men's and women's football tournaments on the opening two days, the hosts commanded a near-capacity 70,000 crowd.
However, the Brazilian side boasting Neymar, Manchester City's new £27 million ($35.4 million) signing Gabriel Jesus and Marquinhos of Paris Saint-Germain did not provide the expected victory procession.
South Africa's Lebo Mothiba had a host of chances to cause an almighty upset, but failed to make a ragged Brazilian defence pay for early nerves. Neymar proudly sported the captain's armband, but his desire to get involved by dropping deep often left him too far from the South African goal to make a telling impact.
The Barcelona star had Brazil's best two efforts of the first-half with strikes from outside the box that forced South African 'keeper Itumeleng Khune into two stunning saves.
South Africa dominated the early stages of the second-half with Mothiba and captain Keagen Dolly coming close. But their chances appeared to have gone when defender Mvala was sent-off for two quickfire yellow cards. Brazil ramped up the pressure.
Jesus somehow turned the ball onto the post with the goal gaping, whilst a dipping drive from Neymar landed on the roof of the net.
However, South Africa resisted to add problems on the field for the hosts to a Games build-up already marred by fears surrounding the Zika virus and Brazil's political turmoil.
Portugal's stunning summer after winning Euro 2016 could get even more golden as they saw off Argentina 2-0 to the delight of the Brazilian crowd in Rio.
Both sides are looking to the future with Lionel Messi having announced his international retirement with Argentina after three final losses and Portuguese hero Cristiano Ronaldo now 31.
Gonzalo Paciencia's low drive put Portugal ahead before a horrible error from Argentina goalkeeper Geronimo Rulli allowed Pite's long-range effort to sneak between his legs to secure the three points six minutes from time.
Honduras beat Algeria 3-2 in the other Group D game. World champions Germany played out a thrilling 2-2 draw with 2012 gold medallists Mexico under a torrential downpour in Salvador.
Three goals in 10 minutes in the second-half put Mexico 2-1 ahead as Oribe Peralta and Rodolfo Pizarro struck either side of Arsenal's Serge Gnabry's reply for Germany.
However, the only World Cup winner on show at the Olympics Matthias Ginter, who flew 20,000km from Borussia Dortmund's pre-season tour in China to Brazil, earned Germany a point. Fiji and South Korea were in action in Group C later.
Nigeria arrived in the Amazonian city of Manaus just hours before their match against Japan as the initial plane intended to take them from their training base in Atlanta on Wednesday was deemed "too small" for the squad and staff. Sweden and Colombia are in action in Manaus in Group B.