Hosts Brazil finally launched their campaign for Olympic gold as sought after starlet Gabriel Barbosa struck twice to defeat Denmark 4-0 on Wednesday, as two-time champions Argentina bowed out of Rio 2016.

Barcelona star Neymar is still yet to hit the net, but played the role of facilitator as Gabriel Jesus and Luan were also on target to end a run of over 200 minutes without a goal after stalemates with Iraq and South Africa got their campaign off to a faltering start.

Freiburg striker Nils Petersen scored five times as world champions Germany smashed Pacific islanders Fiji 10-0 to seal their place in the last eight behind South Korea.